Coordinated device-to-device communications

ABSTRACT

Various aspects of the techniques, methods and devices described in this disclosure relate generally to achieving coexistence between WLAN and P2P networks, and specifically, to coordinated D2D communications. Some aspects particularly involve extending the capabilities of TWT elements transmitted by APs to support periodic reserved access windows during which D2D-enabled wireless devices are permitted to transmit direct wireless communications. Some other aspects relate to sharing time and frequency resources via CAP TDMA or CAP OFDMA techniques, and specifically, to allocating at least some of the time and frequency resources specifically for D2D communications. Some other aspects relate to periodic coordinated access windows during which APs are scheduled to contend but during which D2D devices are not permitted to contend, and specifically, to scheduling a reserved access window within a periodic coordinated access window during which D2D devices may transmit direct communications to other D2D devices despite the permissions associated with the periodic coordinated access windows.

PRIORITY INFORMATION

The present Application for Patent claims priority under 35 U.S.C. § 119to U.S. Provisional Patent Application No. 62/942,292 by Cherian et al.,filed 2 Dec. 2019 and entitled “COORDINATED DEVICE-TO-DEVICECOMMUNICATIONS,” which is assigned to the assignee hereof and herebyexpressly incorporated by reference herein.

TECHNICAL FIELD

This disclosure relates generally to wireless communication, and morespecifically, to coordinating device-to-device communications.

DESCRIPTION OF THE RELATED TECHNOLOGY

A wireless local area network (WLAN) may be formed by one or morewireless access points (APs) that provide a shared wirelesscommunication medium for use by a number of client devices also referredto as wireless stations (STAs). The basic building block of a WLANconforming to the Institute of Electrical and Electronics Engineers(IEEE) 802.11 family of standards is a Basic Service Set (BSS), which ismanaged by an AP. Each BSS is identified by a Basic Service SetIdentifier (BSSID) that is advertised by the AP. An AP periodicallybroadcasts beacon frames to enable any STAs within wireless range of theAP to establish or maintain a communication link with the WLAN.

In addition to participating in a WLAN, STAs may also participate in apeer-to-peer (P2P), ad hoc or mesh network. In such instances, STAs cancommunicate directly with each other via P2P wireless links without theuse of an intermediary AP. In some deployments, regular infrastructuretraffic to and from an AP and an associated set of STAs may interferewith P2P traffic among the STAs, or vice versa. Techniques for achievingcoexistence are desired.

SUMMARY

The systems, methods and devices of this disclosure each have severalinnovative aspects, no single one of which is solely responsible for thedesirable attributes disclosed herein.

The described subject matter relates generally to achieving coexistencebetween WLAN and P2P or ad hoc networks, and particularly, tocoordinated device-to-device (D2D) communications. One innovative aspectof the subject matter described in this disclosure can be implemented asa method of wireless communication. The method may be performed by awireless communication device, operating in or as a first wirelessaccess point, that includes at least one modem, at least one processorcommunicatively coupled with the at least one modem, and at least onememory communicatively coupled with the at least one processor andstoring processor-readable code that, when executed by the at least oneprocessor in conjunction with the at least one modem, is configured toperform the method. The method includes transmitting a first wirelesspacket to at least a first set of wireless stations in a first basicservice set (BSS) controlled by the first wireless access point, eachwireless station in the first set of wireless stations being configuredfor direct wireless communications with other wireless stations, thefirst wireless packet including an indication of periodic reservedaccess windows indicating to the first set of wireless stations thatthey are permitted to transmit direct wireless communications to otherwireless stations in the first set of wireless stations on one or morewireless channels during the periodic reserved access windows. Themethod further includes refraining from transmitting wirelesscommunications during the periodic reserved access windows.

Another innovative aspect of the subject matter described in thisdisclosure can be implemented as a method of wireless communication. Themethod may be performed by a wireless communication device, operating inor as a first wireless station, that includes at least one modem, atleast one processor communicatively coupled with the at least one modem,and at least one memory communicatively coupled with the at least oneprocessor and storing processor-readable code that, when executed by theat least one processor in conjunction with the at least one modem, isconfigured to perform the method. The method includes receiving a firstwireless packet from a first wireless access point that controls a firstBSS including a first set of wireless stations that includes the firstwireless station, the first wireless station being configured for directwireless communications with other wireless stations, the first wirelesspacket including an indication of periodic reserved access windowsindicating to the first wireless station that it is permitted totransmit direct wireless communications to one or more other wirelessstations in the first set of wireless stations on one or more wirelesschannels during the periodic reserved access windows. The method furtherincludes transmitting a second wireless packet directly to anotherwireless station during at least one of the periodic reserved accesswindows.

Another innovative aspect of the subject matter described in thisdisclosure can be implemented as a method of wireless communication. Themethod may be performed by a wireless communication device, operating inor as a first wireless access point, that includes at least one modem,at least one processor communicatively coupled with the at least onemodem, and at least one memory communicatively coupled with the at leastone processor and storing processor-readable code that, when executed bythe at least one processor in conjunction with the at least one modem,is configured to perform the method. The method includes obtaining atransmission opportunity for wireless communication via one or morewireless channels. The method also includes selecting one or more otherwireless access points to participate in the transmission opportunity.The method also includes allocating a respective set of time andfrequency resources of a plurality of sets of time and frequencyresources of the transmission opportunity to each of the first wirelessaccess point and the selected wireless access points. The method alsoincludes allocating a first subset of time and frequency resources, ofthe set of time and frequency resources allocated to the first wirelessaccess point, to a first set of wireless stations in a BSS controlled bythe first wireless access point for direct wireless communications withother wireless stations. The method also includes transmitting a firstwireless packet to the one or more selected wireless access points thatincludes, for each of the selected wireless access points, an indicationof the set of time and frequency resources allocated to the respectivewireless access point. The method additionally includes transmitting asecond wireless packet to the first set of wireless stations thatincludes an indication of the first subset of time and frequencyresources. The method further includes refraining from transmittingwireless communications in the first subset of time and frequencyresources.

Another innovative aspect of the subject matter described in thisdisclosure can be implemented as a method of wireless communication. Themethod may be performed by a wireless communication device, operating inor as a first wireless access point, that includes at least one modem,at least one processor communicatively coupled with the at least onemodem, and at least one memory communicatively coupled with the at leastone processor and storing processor-readable code that, when executed bythe at least one processor in conjunction with the at least one modem,is configured to perform the method. The method includes receiving afirst wireless packet from a second wireless access point that indicatesthat a plurality of time and frequency resources of a transmissionopportunity owned by the second wireless access point can be shared bythe second wireless access point. The method also includes transmittinga second wireless packet to the second wireless access point indicatinga desire to participate in the transmission opportunity. The method alsoincludes receiving a third wireless packet from the second wirelessaccess point that includes an indication of a first set of time andfrequency resources of the plurality of time and frequency resourcesallocated to the first wireless access point and usable by the firstwireless access point to transmit data to, or receive data from, a firstset of wireless stations in a first BSS controlled by the first wirelessaccess point during the transmission opportunity. The method alsoincludes allocating a first subset of time and frequency resources, ofthe first set of time and frequency resources allocated to the firstwireless access point, to the first set of wireless stations for directwireless communications with other wireless stations. The methodadditionally includes transmitting a fourth wireless packet to the firstset of wireless stations that includes an indication of the first subsetof time and frequency resources. The method further includes refrainingfrom transmitting wireless communications in the first subset of timeand frequency resources.

Another innovative aspect of the subject matter described in thisdisclosure can be implemented as a method of wireless communication. Themethod may be performed by a wireless communication device, operating inor as a first wireless station, that includes at least one modem, atleast one processor communicatively coupled with the at least one modem,and at least one memory communicatively coupled with the at least oneprocessor and storing processor-readable code that, when executed by theat least one processor in conjunction with the at least one modem, isconfigured to perform the method. The method includes receiving a firstwireless packet from a first wireless access point that controls a firstBSS including a first set of wireless stations that includes the firstwireless station, the first set of wireless stations being configuredfor direct wireless communications with other wireless stations, thefirst wireless packet including an indication of a first subset of timeand frequency resources of a first set of time and frequency resourcesallocated to the first BSS of a plurality of sets of time and frequencyresources of a transmission opportunity owned by the first wirelessaccess point or a second wireless access point, the first subset of timeand frequency resources being allocated for use by the first set ofwireless stations for direct wireless communications with other wirelessstations. The method further includes transmitting a second wirelesspacket directly to another wireless station using the first subset oftime and frequency resources.

Another innovative aspect of the subject matter described in thisdisclosure can be implemented as a method of wireless communication. Themethod may be performed by a wireless communication device, operating inor as a first wireless access point, that includes at least one modem,at least one processor communicatively coupled with the at least onemodem, and at least one memory communicatively coupled with the at leastone processor and storing processor-readable code that, when executed bythe at least one processor in conjunction with the at least one modem,is configured to perform the method. The method includes exchanging oneor more first wireless packets with a first set of wireless accesspoints that includes the first wireless access point to coordinate aschedule of periodic coordinated access windows during which the firstset of wireless access points are scheduled to contend for access to oneor more wireless channels. The method also includes transmitting asecond wireless packet that includes a first indication of the periodiccoordinated access windows. The method also includes determining that afirst set of wireless stations in a first BSS controlled by the firstwireless access point is operating a neighbor awareness networking (NAN)network, each wireless station in the first set of wireless stationsbeing configured for direct wireless communications with other wirelessstations in the NAN network, the first set of wireless stations notbeing permitted to contend for access to the one or more wirelesschannels during the periodic coordinated access windows. The methodadditionally includes transmitting a third wireless packet to the firstset of wireless stations that includes a second indication of a reservedaccess window within one or more of the periodic coordinated accesswindows, the second indication indicating that the first set of wirelessstations are permitted to transmit direct wireless communications toother wireless stations in the NAN network on the one or more wirelesschannels despite the first indication. The method further includesrefraining from transmitting wireless communications during the reservedaccess windows.

Another innovative aspect of the subject matter described in thisdisclosure can be implemented as a method of wireless communication. Themethod may be performed by a wireless communication device, operating inor as a first wireless station, that includes at least one modem, atleast one processor communicatively coupled with the at least one modem,and at least one memory communicatively coupled with the at least oneprocessor and storing processor-readable code that, when executed by theat least one processor in conjunction with the at least one modem, isconfigured to perform the method. The method includes forming or joininga neighbor awareness networking (NAN) network including a first set ofwireless stations that includes the first wireless station, eachwireless station in the first set of wireless stations being configuredfor direct wireless communications with other wireless stations in theNAN network. The method also includes receiving a first wireless packetfrom a first wireless access point that controls a first BSS thatincludes the first set of wireless stations, the first wireless packetincluding a first indication of periodic coordinated access windowsduring which wireless access points, including the first wireless accesspoint, are scheduled to contend for access to one or more wirelesschannels, and during which wireless stations, including the first set ofwireless stations, are not permitted to contend for access to the one ormore wireless channels. The method additionally includes receiving asecond wireless packet from the first wireless access point thatincludes a second indication of a reserved access window within one ormore of the periodic coordinated access windows, the second indicationindicating that the first set of wireless stations are permitted totransmit direct wireless communications to other wireless stations inthe NAN network on the one or more wireless channels despite the firstindication. The method further includes transmitting a third wirelesspacket directly to another wireless station during at least one of thereserved access windows.

BRIEF DESCRIPTION OF THE DRAWINGS

Details of one or more implementations of the subject matter describedin this disclosure are set forth in the accompanying drawings and thedescription below. However, the accompanying drawings illustrate onlysome typical aspects of this disclosure and are therefore not to beconsidered limiting of its scope. Other features, aspects, andadvantages will become apparent from the description, the drawings andthe claims.

FIG. 1 shows a pictorial diagram of an example wireless communicationnetwork.

FIG. 2A shows an example protocol data unit (PDU) usable forcommunications between an access point (AP) and a number of stations(STAs).

FIG. 2B shows an example field in the PDU of FIG. 2A.

FIG. 3A shows another example PDU usable for communications between anAP and a number of STAs.

FIG. 3B shows another example PDU usable for communications between anAP and a number of STAs.

FIG. 4 shows a pictorial diagram of another example wirelesscommunication network.

FIG. 5 shows a block diagram of an example wireless communicationdevice.

FIG. 6A shows a block diagram of an example access point (AP).

FIG. 6B shows a block diagram of an example station (STA).

FIG. 7 shows a flowchart illustrating an example process for wirelesscommunication that supports coordinated device-to-device (D2D)communications according to some implementations.

FIG. 8 shows a timing diagram illustrating example periodic reservedaccess windows that support coordinated D2D communications according tosome implementations.

FIG. 9 shows a flowchart illustrating an example process for wirelesscommunication that supports coordinated D2D communications according tosome implementations.

FIG. 10 shows a flowchart illustrating an example process for wirelesscommunication that supports coordinated D2D communications according tosome implementations.

FIG. 11 shows a timing diagram illustrating example reserved timeresources that support coordinated D2D communications according to someimplementations.

FIG. 12 shows a timing diagram illustrating example reserved frequencyresources that support coordinated D2D communications according to someimplementations.

FIG. 13 shows a flowchart illustrating an example process for wirelesscommunication that supports coordinated D2D communications according tosome implementations.

FIG. 14 shows a flowchart illustrating an example process for wirelesscommunication that supports coordinated D2D communications according tosome implementations.

FIG. 15 shows a flowchart illustrating an example process for wirelesscommunication that supports coordinated D2D communications according tosome implementations.

FIG. 16 shows a timing diagram illustrating example reserved accesswindows that support coordinated D2D communications according to someimplementations.

FIG. 17 shows a flowchart illustrating an example process for wirelesscommunication that supports coordinated D2D communications according tosome implementations.

FIG. 18 shows a block diagram of an example wireless communicationdevice that supports coordinated D2D communications according to someimplementations.

FIG. 19 shows a block diagram of an example wireless communicationdevice that supports coordinated D2D communications according to someimplementations.

FIG. 20 shows a block diagram of an example wireless communicationdevice that supports coordinated D2D communications according to someimplementations.

FIG. 21 shows a block diagram of an example wireless communicationdevice that supports coordinated D2D communications according to someimplementations.

FIG. 22 shows a block diagram of an example wireless communicationdevice that supports coordinated D2D communications according to someimplementations.

FIG. 23 shows a block diagram of an example wireless communicationdevice that supports coordinated D2D communications according to someimplementations.

FIG. 24 shows a block diagram of an example wireless communicationdevice that supports coordinated D2D communications according to someimplementations.

Like reference numbers and designations in the various drawings indicatelike elements.

DETAILED DESCRIPTION

The following description is directed to some particular implementationsfor the purposes of describing innovative aspects of this disclosure.However, a person having ordinary skill in the art will readilyrecognize that the teachings herein can be applied in a multitude ofdifferent ways. The described implementations can be implemented in anydevice, system or network that is capable of transmitting and receivingradio frequency (RF) signals according to one or more of the Instituteof Electrical and Electronics Engineers (IEEE) 802.11 standards, theIEEE 802.15 standards, the Bluetooth® standards as defined by theBluetooth Special Interest Group (SIG), or the Long Term Evolution(LTE), 3G, 4G or 5G (New Radio (NR)) standards promulgated by the 3rdGeneration Partnership Project (3GPP), among others. The describedimplementations can be implemented in any device, system or network thatis capable of transmitting and receiving RF signals according to one ormore of the following technologies or techniques: code division multipleaccess (CDMA), time division multiple access (TDMA), frequency divisionmultiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA(SC-FDMA), single-user (SU) multiple-input multiple-output (MIMO) andmulti-user (MU) MIMO. The described implementations also can beimplemented using other wireless communication protocols or RF signalssuitable for use in one or more of a wireless personal area network(WPAN), a wireless local area network (WLAN), a wireless wide areanetwork (WWAN), or an internet of things (IOT) network.

Various aspects of the techniques, methods and devices disclosed hereinrelate generally to achieving coexistence between WLAN and peer-to-peer(P2P) or ad hoc networks, and specifically, to coordinateddevice-to-device (D2D) communications. Some aspects particularly involveextending the capabilities of target wake time (TWT) elementstransmitted by wireless access points to support periodic reservedaccess windows during which D2D-enabled wireless devices are permittedto transmit direct wireless communications to other D2D-enabled wirelessdevices.

Some other aspects relate to sharing time and frequency resources of awireless medium, and more particularly, coordinated access point (CAP)time-division-multiple-access (TDMA) or CAPorthogonal-frequency-division-multiple-access (OFDMA) techniques forsharing the time and frequency resources of a transmission opportunity.According to such techniques, a wireless access point that winscontention and gains access to the wireless medium for the duration of aTXOP may share its time and frequency resources with other coordinatedaccess points. The coordinated access points may then specificallyallocate at least some of the time and frequency resources in theirrespective time and frequency resources specifically for D2Dcommunications.

In some other aspects, a D2D-enabled wireless device may form or join aP2P network that also includes a first set of other D2D-enabled wirelessdevices. The D2D-enabled wireless device may receive a first indicationfrom a wireless access point that indicates periodic coordinated accesswindows during which wireless access points are scheduled to contend foraccess and during which the set of D2D-enables wireless devices are notpermitted to contend for access. The D2D-enabled wireless device mayalso receive a second indication of a reserved access window within oneor more of the periodic coordinated access windows during which at leastsome of the set of D2D-enabled wireless devices are permitted totransmit direct wireless communications to other D2D-enabled wirelessdevices network despite the permissions associated with the firstindication.

FIG. 1 shows a block diagram of an example wireless communicationnetwork 100. According to some aspects, the wireless communicationnetwork 100 can be an example of a wireless local area network (WLAN)such as a Wi-Fi network (and will hereinafter be referred to as WLAN100). For example, the WLAN 100 can be a network implementing at leastone of the IEEE 802.11 family of wireless communication protocolstandards (such as that defined by the IEEE 802.11-2016 specification oramendments thereof including, but not limited to, 802.11ay, 802.11ax,802.11az, 802.11ba and 802.11be). The WLAN 100 may include numerouswireless communication devices such as an access point (AP) 102 andmultiple stations (STAs) 104. While only one AP 102 is shown, the WLANnetwork 100 also can include multiple APs 102.

Each of the STAs 104 also may be referred to as a mobile station (MS), amobile device, a mobile handset, a wireless handset, an access terminal(AT), a user equipment (UE), a subscriber station (SS), or a subscriberunit, among other possibilities. The STAs 104 may represent variousdevices such as mobile phones, personal digital assistant (PDAs), otherhandheld devices, netbooks, notebook computers, tablet computers,laptops, display devices (for example, TVs, computer monitors,navigation systems, among others), music or other audio or stereodevices, remote control devices (“remotes”), printers, kitchen or otherhousehold appliances, key fobs (for example, for passive keyless entryand start (PKES) systems), among other possibilities.

A single AP 102 and an associated set of STAs 104 may be referred to asa basic service set (BSS), which is managed by the respective AP 102.FIG. 1 additionally shows an example coverage area 106 of the AP 102,which may represent a basic service area (BSA) of the WLAN 100. The BSSmay be identified to users by a service set identifier (SSID), as wellas to other devices by a basic service set identifier (BSSID), which maybe a medium access control (MAC) address of the AP 102. The AP 102periodically broadcasts beacon frames (“beacons”) including the BSSID toenable any STAs 104 within wireless range of the AP 102 to “associate”or re-associate with the AP 102 to establish a respective communicationlink 108 (hereinafter also referred to as a “Wi-Fi link”), or tomaintain a communication link 108, with the AP 102. For example, thebeacons can include an identification of a primary channel used by therespective AP 102 as well as a timing synchronization function forestablishing or maintaining timing synchronization with the AP 102. TheAP 102 may provide access to external networks to various STAs 104 inthe WLAN via respective communication links 108.

To establish a communication link 108 with an AP 102, each of the STAs104 is configured to perform passive or active scanning operations(“scans”) on frequency channels in one or more frequency bands (forexample, the 2.4 GHz, 5 GHz, 6 GHz or 60 GHz bands). To perform passivescanning, a STA 104 listens for beacons, which are transmitted byrespective APs 102 at a periodic time interval referred to as the targetbeacon transmission time (TBTT) (measured in time units (TUs) where oneTU may be equal to 1024 microseconds (μs)). To perform active scanning,a STA 104 generates and sequentially transmits probe requests on eachchannel to be scanned and listens for probe responses from APs 102. EachSTA 104 may be configured to identify or select an AP 102 with which toassociate based on the scanning information obtained through the passiveor active scans, and to perform authentication and associationoperations to establish a communication link 108 with the selected AP102. The AP 102 assigns an association identifier (AID) to the STA 104at the culmination of the association operations, which the AP 102 usesto track the STA 104.

As a result of the increasing ubiquity of wireless networks, a STA 104may have the opportunity to select one of many BSSs within range of theSTA or to select among multiple APs 102 that together form an extendedservice set (ESS) including multiple connected BSSs. An extended networkstation associated with the WLAN 100 may be connected to a wired orwireless distribution system that may allow multiple APs 102 to beconnected in such an ESS. As such, a STA 104 can be covered by more thanone AP 102 and can associate with different APs 102 at different timesfor different transmissions. Additionally, after association with an AP102, a STA 104 also may be configured to periodically scan itssurroundings to find a more suitable AP 102 with which to associate. Forexample, a STA 104 that is moving relative to its associated AP 102 mayperform a “roaming” scan to find another AP 102 having more desirablenetwork characteristics such as a greater received signal strengthindicator (RSSI) or a reduced traffic load.

In some cases, STAs 104 may form networks without APs 102 or otherequipment other than the STAs 104 themselves. One example of such anetwork is an ad hoc network (or wireless ad hoc network). Ad hocnetworks may alternatively be referred to as mesh networks orpeer-to-peer (P2P) networks. In some cases, ad hoc networks may beimplemented within a larger wireless network such as the WLAN 100. Insuch implementations, while the STAs 104 may be capable of communicatingwith each other through the AP 102 using communication links 108, STAs104 also can communicate directly with each other via direct wirelesslinks 110. Additionally, two STAs 104 may communicate via a directcommunication link 110 regardless of whether both STAs 104 areassociated with and served by the same AP 102. In such an ad hoc system,one or more of the STAs 104 may assume the role filled by the AP 102 ina BSS. Such a STA 104 may be referred to as a group owner (GO) and maycoordinate transmissions within the ad hoc network. Examples of directwireless links 110 include Wi-Fi Direct connections, connectionsestablished by using a Wi-Fi Tunneled Direct Link Setup (TDLS) link, andother P2P group connections.

The APs 102 and STAs 104 may function and communicate (via therespective communication links 108) according to the IEEE 802.11 familyof wireless communication protocol standards (such as that defined bythe IEEE 802.11-2016 specification or amendments thereof including, butnot limited to, 802.11ay, 802.11ax, 802.11az, 802.11ba and 802.11be).These standards define the WLAN radio and baseband protocols for the PHYand medium access control (MAC) layers. The APs 102 and STAs 104transmit and receive wireless communications (hereinafter also referredto as “Wi-Fi communications”) to and from one another in the form of PHYprotocol data units (PPDUs) (or physical layer convergence protocol(PLCP) PDUs). The APs 102 and STAs 104 in the WLAN 100 may transmitPPDUs over an unlicensed spectrum, which may be a portion of spectrumthat includes frequency bands traditionally used by Wi-Fi technology,such as the 2.4 GHz band, the 5 GHz band, the 60 GHz band, the 3.6 GHzband, and the 900 MHz band. Some implementations of the APs 102 and STAs104 described herein also may communicate in other frequency bands, suchas the 6 GHz band, which may support both licensed and unlicensedcommunications. The APs 102 and STAs 104 also can be configured tocommunicate over other frequency bands such as shared licensed frequencybands, where multiple operators may have a license to operate in thesame or overlapping frequency band or bands.

Each of the frequency bands may include multiple sub-bands or frequencychannels. For example, PPDUs conforming to the IEEE 802.11n, 802.11ac,802.11ax and 802.11be standard amendments may be transmitted over the2.4, 5 GHz or 6 GHz bands, each of which is divided into multiple 20 MHzchannels. As such, these PPDUs are transmitted over a physical channelhaving a minimum bandwidth of 20 MHz, but larger channels can be formedthrough channel bonding. For example, PPDUs may be transmitted overphysical channels having bandwidths of 40 MHz, 80 MHz, 160 or 320 MHz bybonding together multiple 20 MHz channels.

Each PPDU is a composite structure that includes a PHY preamble and apayload in the form of a PHY service data unit (PSDU). The informationprovided in the preamble may be used by a receiving device to decode thesubsequent data in the PSDU. In instances in which PPDUs are transmittedover a bonded channel, the preamble fields may be duplicated andtransmitted in each of the multiple component channels. The PHY preamblemay include both a legacy portion (or “legacy preamble”) and anon-legacy portion (or “non-legacy preamble”). The legacy preamble maybe used for packet detection, automatic gain control and channelestimation, among other uses. The legacy preamble also may generally beused to maintain compatibility with legacy devices. The format of,coding of, and information provided in the non-legacy portion of thepreamble is based on the particular IEEE 802.11 protocol to be used totransmit the payload.

FIG. 2A shows an example protocol data unit (PDU) 200 usable forwireless communication between an AP and a number of STAs. For example,the PDU 200 can be configured as a PPDU. As shown, the PDU 200 includesa PHY preamble 202 and a PHY payload 204. For example, the preamble 202may include a legacy portion that itself includes a legacy shorttraining field (L-STF) 206, which may consist of two BPSK symbols, alegacy long training field (L-LTF) 208, which may consist of two BPSKsymbols, and a legacy signal field (L-SIG) 210, which may consist of twoBPSK symbols. The legacy portion of the preamble 202 may be configuredaccording to the IEEE 802.11a wireless communication protocol standard.The preamble 202 may also include a non-legacy portion including one ormore non-legacy fields 212, for example, conforming to an IEEE wirelesscommunication protocol such as the IEEE 802.11ac, 802.11ax, 802.11be orlater wireless communication protocol standards.

The L-STF 206 generally enables a receiving device to perform automaticgain control (AGC) and coarse timing and frequency estimation. The L-LTF208 generally enables a receiving device to perform fine timing andfrequency estimation and also to perform an initial estimate of thewireless channel. The L-SIG 210 generally enables a receiving device todetermine a duration of the PDU and to use the determined duration toavoid transmitting on top of the PDU. For example, the L-STF 206, theL-LTF 208 and the L-SIG 210 may be modulated according to a binary phaseshift keying (BPSK) modulation scheme. The payload 204 may be modulatedaccording to a BPSK modulation scheme, a quadrature BPSK (Q-BPSK)modulation scheme, a quadrature amplitude modulation (QAM) modulationscheme, or another appropriate modulation scheme. The payload 204 mayinclude a PSDU including a data field (DATA) 214 that, in turn, maycarry higher layer data, for example, in the form of medium accesscontrol (MAC) protocol data units (MPDUs) or an aggregated MPDU(A-MPDU).

FIG. 2B shows an example L-SIG 210 in the PDU 200 of FIG. 2A. The L-SIG210 includes a data rate field 222, a reserved bit 224, a length field226, a parity bit 228, and a tail field 230. The data rate field 222indicates a data rate (note that the data rate indicated in the datarate field 212 may not be the actual data rate of the data carried inthe payload 204). The length field 226 indicates a length of the packetin units of, for example, symbols or bytes. The parity bit 228 may beused to detect bit errors. The tail field 230 includes tail bits thatmay be used by the receiving device to terminate operation of a decoder(for example, a Viterbi decoder). The receiving device may utilize thedata rate and the length indicated in the data rate field 222 and thelength field 226 to determine a duration of the packet in units of, forexample, microseconds (μs) or other time units.

FIG. 3A shows another example PDU 300 usable for wireless communicationbetween an AP and a number of STAs. The PDU 300 may be used for MU-OFDMAor MU-MIMO transmissions. The PDU 300 includes a PHY preamble includinga legacy portion 302 and a non-legacy portion 304. The PDU 300 mayfurther include a PHY payload 306 after the preamble, for example, inthe form of a PSDU including a DATA field 324. The legacy portion 302 ofthe preamble includes L-STF 308, L-LTF 310, and L-SIG 312. Thenon-legacy portion 304 of the preamble and the DATA field 374 may beformatted as a High Efficiency (HE) WLAN preamble and frame,respectively, in accordance with the IEEE 802.11ax amendment to the IEEE802.11 wireless communication protocol standard. The non-legacy portion304 includes a repeated legacy signal field (RL-SIG) 314, a first HEsignal field (HE-SIG-A) 316, a second HE signal field (HE-SIG-B) 318encoded separately from HE-SIG-A 316, an HE short training field(HE-STF) 320 and a number of HE long training fields (HE-LTFs) 322. Likethe L-STF 308, L-LTF 310, and L-SIG 312, the information in RL-SIG 314and HE-SIG-A 316 may be duplicated and transmitted in each of thecomponent 20 MHz channels in instances involving the use of a bondedchannel. In contrast, HE-SIG-B 318 may be unique to each 20 MHz channeland may target specific STAs 104.

RL-SIG 314 may indicate to HE-compatible STAs 104 that the PPDU is an HEPPDU. An AP 102 may use HE-SIG-A 316 to identify and inform multipleSTAs 104 that the AP has scheduled UL or DL resources for them. HE-SIG-A316 may be decoded by each HE-compatible STA 104 served by the AP 102.HE-SIG-A 316 includes information usable by each identified STA 104 todecode an associated HE-SIG-B 318. For example, HE-SIG-A 316 mayindicate the frame format, including locations and lengths of HE-SIG-Bs318, available channel bandwidths, modulation and coding schemes (MCSs),among other possibilities. HE-SIG-A 316 also may include HE WLANsignaling information usable by STAs 104 other than the number ofidentified STAs 104.

HE-SIG-B 318 may carry STA-specific scheduling information such as, forexample, per-user MCS values and per-user RU allocation information. Inthe context of DL MU-OFDMA, such information enables the respective STAs104 to identify and decode corresponding RUs in the associated datafield. Each HE-SIG-B 318 includes a common field and at least oneSTA-specific (“user-specific”) field. The common field can indicate RUdistributions to multiple STAs 104, indicate the RU assignments in thefrequency domain, indicate which RUs are allocated for MU-MIMOtransmissions and which RUs correspond to MU-OFDMA transmissions, andthe number of users in allocations, among other possibilities. Thecommon field may be encoded with common bits, CRC bits, and tail bits.The user-specific fields are assigned to particular STAs 104 and may beused to schedule specific RUs and to indicate the scheduling to otherWLAN devices. Each user-specific field may include multiple user blockfields (which may be followed by padding). Each user block field mayinclude two user fields that contain information for two respective STAsto decode their respective RU payloads in DATA field 324.

FIG. 3B shows an example PPDU 350 usable for wireless communicationbetween an AP and a number of STAs according to some implementations.The PPDU 350 may be used for SU, MU-OFDMA or MU-MIMO transmissions. ThePPDU 350 includes a PHY preamble including a legacy portion 352 and anon-legacy portion 354. The PPDU 350 may further include a PHY payload356 after the preamble, for example, in the form of a PSDU including aDATA field 376. The legacy portion 352 includes L-STF 358, L-LTF 360,and L-SIG 362. The non-legacy portion 354 of the preamble and the DATAfield 376 may be formatted as an Extreme High Throughput (EHT) WLANpreamble and frame, respectively, in accordance with the IEEE 802.11beamendment to the IEEE 802.11 wireless communication protocol standard,or may be formatted as a preamble and frame, respectively, conforming toany later (post-HE) version of a new wireless communication protocolconforming to a future IEEE 802.11 wireless communication protocolstandard or other standard.

The non-legacy portion 354 of the preamble includes a second signalfield (referred to herein as “Pre-SIG”) 366, a third signal field(referred to herein as “EHT-SIG-A” although it may be structured as, andcarry version-dependent information for, other wireless communicationprotocol versions beyond EHT) 368, and a fourth signal field (referredto herein as “EHT-SIG-B” although it may be structured as, and carryversion-dependent information for, other wireless communication protocolversions beyond EHT) 370. The non-legacy portion 354 further includes anadditional short training field (referred to herein as “EHT-STF”although it may be structured as, and carry version-dependentinformation for, other wireless communication protocol versions beyondEHT) 372 and a number of additional long training fields (referred toherein as “EHT-LTFs” although they may be structured as, and carryversion-dependent information for, other wireless communication protocolversions beyond EHT) 374. Like L-STF 358, L-LTF 360, and L-SIG 362, theinformation in Pre-SIG 366 and EHT-SIG-A 368 may be duplicated andtransmitted in each of the component 20 MHz channels in instancesinvolving the use of a bonded channel. In some implementations,EHT-SIG-A 368 may additionally or alternatively carry information in oneor more non-primary 20 MHz channels that is different than theinformation carried in the primary 20 MHz channel. EHT-SIG-B 370 may beunique to each 20 MHz channel and, as described above, may targetspecific STAs 104. The non-legacy portion 354 of the preamble may or maynot include a repeated legacy signal field (RL-SIG) 364 after L-SIG 362and before Pre-SIG 366.

EHT-SIG-A 368 may include one or more jointly encoded symbols and may beencoded in a different block from the block in which Pre-SIG 366 isencoded. EHT-SIG-A 368 may be used by an AP to identify and informmultiple STAs 104 that the AP has scheduled UL or DL resources.EHT-SIG-A 368 may be decoded by each compatible STA 104 served by the AP102. EHT-SIG-A 368 includes information usable by the identified STAs104 to decode an associated EHT-SIG-B 370. EHT-SIG-A 368 may generallybe used by a receiving device to interpret bits in EHT-SIG-B 370 or DATAfield 376. For example, EHT-SIG-A 368 may indicate the locations andlengths of EHT-SIG-Bs 370 in the various component channels, availablechannel bandwidths, and modulation and coding schemes (MCSs), amongother possibilities. EHT-SIG-A 368 may further include a cyclicredundancy check (CRC) (for example, four bits) and a tail (for example,6 bits) that may be used for binary convolutional code (BCC).

EHT-SIG-B 370 may include multiple symbols that may be encoded in adifferent block from the block in which EHT-SIG-A 368 is encoded. Insome other implementations, EHT-SIG-A 368 may be jointly encoded withsome or all of EHT-SIG-B 370. For example, EHT-SIG-A 368 may be jointlyencoded with a first portion of EHT-SIG-B 370 that includes informationcommon to all users served by the PPDU 350. EHT-SIG-B 370 may carrySTA-specific scheduling information such as, for example, per-user MCSvalues and per-user RU allocation information. EHT-SIG-B 370 maygenerally be used by a receiving device to interpret bits in the DATAfield 376. In the context of DL MU-OFDMA, such information enables therespective STAs 104 to identify and decode corresponding RUs in theassociated DATA field 376. Each EHT-SIG-B 370 includes a common fieldand at least one STA-specific (“user-specific”) field. The common fieldcan indicate RU distributions to multiple STAs 104, indicate the RUassignments in the frequency domain, indicate which RUs are allocatedfor MU-MIMO transmissions and which RUs correspond to MU-OFDMAtransmissions, and the number of users in allocations, among otherpossibilities. The common field may be encoded with common bits, CRCbits, and tail bits. The user-specific fields are assigned to particularSTAs 104 and may be used to schedule specific RUs and to indicate thescheduling to other WLAN devices. Each user-specific field may includemultiple user block fields (which may be followed by padding). Each userblock field may include, for example, two user fields that containinformation for two respective STAs to decode their respective RUpayloads.

Pre-SIG 366, and RL-SIG 364 if present, may indicate to EHT- or laterversion-compliant STAs 104 that the PPDU 350 is an EHT PPDU or a PPDUconforming to another non-legacy wireless communication protocolversion. For example, Pre-SIG 366 may be used by a receiving device tointerpret bits in one or more of EHT-SIG-A 368, EHT-SIG-B 370 or theDATA field 376. In some implementations, Pre-SIG 366 may include areserved bit that indicates whether the PPDU 350 is, for example,compliant with EHT or a later version (for example, after IEEE 802.11ax)of the IEEE 802.11 family of wireless communication protocol standardsor other standards. In some implementations, Pre-SIG 366 includes aversion field that includes at least one bit indicating the particularwireless communication protocol version to which the PPDU 350 conforms.

Access to the shared wireless medium is generally governed by adistributed coordination function (DCF). With a DCF, there is generallyno centralized master device allocating time and frequency resources ofthe shared wireless medium. On the contrary, before a wirelesscommunication device, such as an AP 102 or a STA 104, is permitted totransmit data, it must wait for a particular time and then contend foraccess to the wireless medium. In some implementations, the wirelesscommunication device may be configured to implement the DCF through theuse of carrier sense multiple access (CSMA) with collision avoidance(CA) (CSMA/CA) techniques and timing intervals. Before transmittingdata, the wireless communication device may perform a clear channelassessment (CCA) and determine that the appropriate wireless channel isidle. The CCA includes both physical (PHY-level) carrier sensing andvirtual (MAC-level) carrier sensing. Physical carrier sensing isaccomplished via a measurement of the received signal strength of avalid frame, which is then compared to a threshold to determine whetherthe channel is busy. For example, if the received signal strength of adetected preamble is above a threshold, the medium is considered busy.Physical carrier sensing also includes energy detection. Energydetection involves measuring the total energy the wireless communicationdevice receives regardless of whether the received signal represents avalid frame. If the total energy detected is above a threshold, themedium is considered busy. Virtual carrier sensing is accomplished viathe use of a network allocation vector (NAV), an indicator of a timewhen the medium may next become idle. The NAV is reset each time a validframe is received that is not addressed to the wireless communicationdevice. The NAV effectively serves as a time duration that must elapsebefore the wireless communication device may contend for access even inthe absence of a detected symbol or even if the detected energy is belowthe relevant threshold.

As described above, the DCF is implemented through the use of timeintervals. These time intervals include the time slot time (or “timeslot interval”) and the inter-frame space (IFS). The time slot time isthe basic unit of timing and may be determined based on one or more of atransmit-receive turnaround time, a channel sensing time, a propagationdelay and a MAC processing time. Measurements for channel sensing areperformed for each time slot. All transmissions may begin at time slotboundaries. Different varieties of IFS exist including the short IFS(SIFS), the distributed IFS (DIFS), the extended IFS (EIFS), and thearbitration IFS (AIFS). For example, the DIFS may be defined as the sumof the SIFS and two times the time slot time. The values for the timeslot time and IFS may be provided by a suitable standard specification,such as one of the IEEE 802.11 family of wireless communication protocolstandards (such as that defined by the IEEE 802.11-2016 specification oramendments thereof including, but not limited to, 802.11ay, 802.11ax,802.11az, 802.11ba and 802.11be).

When the NAV reaches 0, the wireless communication device performs thephysical carrier sensing. If the channel remains idle for theappropriate IFS (for example, the DIFS), the wireless communicationdevice initiates a backoff timer, which represents a duration of timethat the device must sense the medium to be idle before it is permittedto transmit. The backoff timer is decremented by one time slot each timethe medium is sensed to be idle during a corresponding time slotinterval. If the channel remains idle until the backoff timer expires,the wireless communication device becomes the holder (or “owner”) of atransmit opportunity (TXOP) and may begin transmitting. The TXOP is theduration of time the wireless communication device can transmit framesover the channel after it has won contention for the wireless medium.If, on the other hand, one or more of the carrier sense mechanismsindicate that the channel is busy, a MAC controller within the wirelesscommunication device will not permit transmission.

Each time the wireless communication devices generates a new PPDU fortransmission in a new TXOP, it randomly selects a new backoff timerduration. The available distribution of the numbers that may be randomlyselected for the backoff timer is referred to as the contention window(CW). If, when the backoff timer expires, the wireless communicationdevice transmits the PPDU, but the medium is still busy, there may be acollision. Additionally, if there is otherwise too much energy on thewireless channel resulting in a poor signal-to-noise ratio (SNR), thecommunication may be corrupted or otherwise not successfully received.In such instances, the wireless communication device may not receive acommunication acknowledging the transmitted PDU within a timeoutinterval. The MAC may then increase the CW exponentially, for example,doubling it, and randomly select a new backoff timer duration from theCW before each attempted retransmission of the PPDU. Before eachattempted retransmission, the wireless communication device may wait aduration of DIFS and, if the medium remains idle, then proceed toinitiate the new backoff timer. There are different CW and TXOPdurations for each of the four access categories (ACs): voice (AC_VO),video (AC_VI), background (AC_BK), and best effort (AC_BE). This enablesparticular types of traffic to be prioritized in the network.

As described above, APs 102 and STAs 104 can support multi-user (MU)communications; that is, concurrent transmissions from one device toeach of multiple devices (for example, multiple simultaneous downlink(DL) communications from an AP 102 to corresponding STAs 104), orconcurrent transmissions from multiple devices to a single device (forexample, multiple simultaneous uplink (UL) transmissions fromcorresponding STAs 104 to an AP 102). To support the MU transmissions,the APs 102 and STAs 104 may utilize multi-user multiple-input,multiple-output (MU-MIMO) and multi-user orthogonal frequency divisionmultiple access (MU-OFDMA) techniques.

In MU-OFDMA schemes, the available frequency spectrum of the wirelesschannel may be divided into multiple resource units (RUs) each includinga number of different frequency subcarriers (“tones”). Different RUs maybe allocated or assigned by an AP 102 to different STAs 104 atparticular times. The sizes and distributions of the RUs may be referredto as an RU allocation. In some implementations, RUs may be allocated in2 MHz intervals, and as such, the smallest RU may include 26 tonesconsisting of 24 data tones and 2 pilot tones. Consequently, in a 20 MHzchannel, up to 9 RUs (such as 2 MHz, 26-tone RUs) may be allocated(because some tones are reserved for other purposes). Similarly, in a160 MHz channel, up to 74 RUs may be allocated. Larger 52 tone, 106tone, 242 tone, 484 tone and 996 tone RUs may also be allocated.Adjacent RUs may be separated by a null subcarrier (such as a DCsubcarrier), for example, to reduce interference between adjacent RUs,to reduce receiver DC offset, and to avoid transmit center frequencyleakage.

For UL MU transmissions, an AP 102 can transmit a trigger frame toinitiate and synchronize an UL MU-OFDMA or UL MU-MIMO transmission frommultiple STAs 104 to the AP 102. Such trigger frames may thus enablemultiple STAs 104 to send UL traffic to the AP 102 concurrently in time.A trigger frame may address one or more STAs 104 through respectiveassociation identifiers (AIDs), and may assign each AID (and thus eachSTA 104) one or more RUs that can be used to send UL traffic to the AP102. The AP also may designate one or more random access (RA) RUs thatunscheduled STAs 104 may contend for.

FIG. 4 shows a pictorial diagram of another example wirelesscommunication network 400. According to some aspects, the wirelesscommunication network 400 can be an example of a WLAN. For example, thewireless network 400 can be a network implementing at least one of theIEEE 802.11 family of standards. The wireless network 400 may includemultiple STAs 404. As described above, each of the STAs 404 also may bereferred to as a mobile station (MS), a mobile device, a mobile handset,a wireless handset, an access terminal (AT), a user equipment (UE), asubscriber station (SS), or a subscriber unit, among otherpossibilities. The STAs 404 may represent various devices such as mobilephones, personal digital assistant (PDAs), other handheld devices,netbooks, notebook computers, tablet computers, laptops, display devices(for example, TVs, computer monitors, navigation systems, among others),music or other audio or stereo devices, remote control devices(“remotes”), printers, kitchen or other household appliances, key fobs(for example, for passive keyless entry and start (PKES) systems), amongother possibilities.

The wireless network 400 is an example of a peer-to-peer (P2P), ad hocor mesh network. STAs 404 can communicate directly with each other viaP2P wireless links 410 (without the use of an intermediary AP). In someimplementations, the wireless network 400 is an example of a neighborawareness networking (NAN) network. NAN networks operate in accordancewith the Wi-Fi Alliance (WFA) Neighbor Awareness Networking (alsoreferred to as NAN) standard specification. NAN-compliant STAs 404(hereinafter also simply “NAN devices 404”) transmit and receive NANcommunications (for example, in the form of Wi-Fi packets includingframes conforming to an IEEE 802.11 wireless communication protocolstandard such as that defined by the IEEE 802.11-2016 specification oramendments thereof including, but not limited to, 802.11ay, 802.11ax,802.11az, 802.11ba and 802.11be) to and from one another via wirelessP2P links 410 (hereinafter also referred to as “NAN links”) using a datapacket routing protocol, such as Hybrid Wireless Mesh Protocol (HWMP),for path selection.

A NAN network generally refers to a collection of NAN devices that sharea common set of NAN parameters including: the time period betweenconsecutive discovery windows, the time duration of the discoverywindows, the NAN beacon interval, and the NAN discovery channel(s). ANAN ID is an identifier signifying a specific set of NAN parameters foruse within the NAN network. NAN networks are dynamically self-organizedand self-configured. NAN devices 404 in the network automaticallyestablish an ad-hoc network with other NAN devices 404 such that networkconnectivity can be maintained. Each NAN device 404 is configured torelay data for the NAN network such that various NAN devices 404 maycooperate in the distribution of data within the network. As a result, amessage can be transmitted from a source NAN device to a destination NANdevice by being propagated along a path, hopping from one NAN device tothe next until the destination is reached.

Each NAN device 404 is configured to transmit two types of beacons: NANdiscovery beacons and NAN synchronization beacons. When a NAN device 404is turned on, or otherwise when NAN-functionality is enabled, the NANdevice periodically transmits NAN discovery beacons (for example, every100 TUs, every 128 TUs or another suitable period) and NANsynchronization beacons (for example, every 512 TUs or another suitableperiod). Discovery beacons are management frames, transmitted betweendiscovery windows, used to facilitate the discovery of NAN clusters. ANAN cluster is a collection of NAN devices within a NAN network that aresynchronized to the same clock and discovery window schedule using atime synchronization function (TSF). To join NAN clusters, NAN devices404 passively scan for discovery beacons from other NAN devices. Whentwo NAN devices 404 come within a transmission range of one another,they will discover each other based on such discovery beacons.Respective master preference values determine which of the NAN devices404 will become the master device. If a NAN cluster is not discovered, aNAN device 404 may start a new NAN cluster. When a NAN device 404 startsa NAN cluster, it assumes the master role and broadcasts a discoverybeacon. Additionally, a NAN device may choose to participate in morethan one NAN cluster within a NAN network.

The links between the NAN devices 404 in a NAN cluster are associatedwith discovery windows—the times and channel on which the NAN devicesconverge. At the beginning of each discovery window, one or more NANdevices 404 may transmit a NAN synchronization beacon, which is amanagement frame used to synchronize the timing of the NAN deviceswithin the NAN cluster to that of the master device. The NAN devices 404may then transmit multicast or unicast NAN service discovery framesdirectly to other NAN devices within the service discovery threshold andin the same NAN cluster during the discovery window. The servicediscovery frames indicate services supported by the respective NANdevices 404.

In some instances, NAN devices 404 may exchange service discovery framesto ascertain whether both devices support ranging operations. NANdevices 404 may perform such ranging operations (“ranging”) during thediscovery windows. The ranging may involve an exchange of fine timingmeasurement (FTM) frames (such as those defined in IEEE 802.11-REVmc).For example, a first NAN device 404 may transmit unicast FTM requests tomultiple peer NAN devices 404. The peer NAN devices 404 may thentransmit responses to the first NAN device 404. The first NAN device 404may then exchange a number of FTM frames with each of the peer NANdevices 404. The first NAN device 404 may then determine a range betweenitself and each of the peer devices 404 based on the FTM frames andtransmit a range indication to each of the peer NAN devices 404. Forexample, the range indication may include a distance value or anindication as to whether a peer NAN device 404 is within a servicediscovery threshold (for example, 3 meters(m)) of the first NAN device404. NAN links between NAN devices within the same NAN cluster maypersist over multiple discovery windows as long as the NAN devicesremain within the service discovery thresholds of one another andsynchronized to the anchor master of the NAN cluster.

Some NAN devices 404 also may be configured for wireless communicationwith other networks such as with a Wi-Fi WLAN or a wireless (forexample, cellular) wide area network (WWAN), which may, in turn, provideaccess to external networks including the Internet. For example, a NANdevice 404 may be configured to associate and communicate, via a Wi-Fior cellular link 212, with an AP or base station 202 of a WLAN or WWANnetwork, respectively. In such instances, the NAN device 404 may includesoftware-enabled access point (SoftAP) functionality enabling the STA tooperate as a Wi-Fi hotspot to provide other NAN devices 404 with accessto the external networks via the associated WLAN or WWAN backhaul. Sucha NAN device 404 (referred to as a NAN concurrent device) is capable ofoperating in both a NAN network as well as another type of wirelessnetwork, such as a Wi-Fi BSS. In some such implementations, a NAN device404 may, in a service discovery frame, advertise an ability to providesuch access point services to other NAN devices 404.

There are two general NAN service discovery messages: publish messagesand subscribe messages. Generally, publishing is a mechanism for anapplication on a NAN device to make selected information about thecapabilities and services of the NAN device available to other NANdevices, while subscribing is a mechanism for an application on a NANdevice to gather selected types of information about the capabilitiesand services of other NAN devices. A NAN device may generate andtransmit a subscribe message when requesting other NAN devices operatingwithin the same NAN cluster to provide a specific service. For example,in an active subscriber mode, a subscribe function executing within theNAN device may transmit a NAN service discovery frame to actively seekthe availability of specific services. A publish function executingwithin a publishing NAN device capable of providing a requested servicemay, for example, transmit a publish message to reply to the subscribingNAN device responsive to the satisfaction of criteria specified in thesubscribe message. The publish message may include a range parameterindicating the service discovery threshold, which represents the maximumdistance at which a subscribing NAN device can avail itself of theservices of the publishing NAN device. A NAN also may use a publishmessage in an unsolicited manner, for example, a publishing NAN devicemay generate and transmit a publish message to make its servicesdiscoverable for other NAN devices operating within the same NANcluster. In a passive subscriber mode, the subscribe function does notinitiate the transfer of any subscribe message, rather, the subscribefunction looks for matches in received publish messages to determine theavailability of desired services.

Subsequent to a discovery window is a transmission opportunity period.This period includes numerous resource blocks. A NAN device link (NDL)refers to the negotiated resource blocks between NAN devices used forNAN operations. An NDL can include more than one “hop.” The number ofhops depends on the number of devices between the device providing theservice and the device consuming or subscribing to the service. Anexample of an NDL that includes two hops includes three NAN devices: theprovider, the subscriber and a proxy to relay the information betweenthe provider and the subscriber. In such a configuration, the first hoprefers to the communication of information between the provider and theproxy, and the second hop refers to the communication of the informationbetween the proxy and the subscriber. An NDL may refer to a subset ofNAN devices capable of one-hop service discovery, but an NDL also may becapable of service discovery and subscription over multiple hops (amulti-hop NDL).

There are two general NDL types: paged NDL (P-NDL) and synchronized NDL(S-NDL). Each common resource block (CRB) of a P-NDL includes a pagingwindow (PW) followed by a transmission window (TxW). All NAN devicesparticipating in a P-NDL operate in a state to receive frames during thepaging window. Generally, the participating NAN devices wake up duringthe paging window to listen on the paging channel to determine whetherthere is any traffic buffered for the respective devices. For example, aNAN device that has pending data for transmission to another NAN devicemay transmit a traffic announcement message to the other NAN deviceduring the paging window to inform the other NAN device of the buffereddata. If there is data available, the NAN device remains awake duringthe transmission window to exchange the data. If there is no data tosend, the NAN device may transition back to a sleep state during thetransmission window to conserve power. A NAN device transmits a pagingmessage to its NDL peer during a paging window if it has buffered dataavailable for the peer. The paging message includes, for example, theMAC addresses or identifiers of the destination devices for which datais available. A NAN device that is listed as a recipient in a receivedpaging message transmits a trigger frame to the transmitting device andremains awake during the subsequent transmission window to receive thedata. The NDL transmitter device transmits the buffered data during thetransmission window to the recipient devices from whom it received atrigger frame. A NAN device that establishes an S-NDL with a peer NANdevice may transmit data frames to the peer from the beginning of eachS-NDL CRB without transmitting a paging message in advance.

FIG. 5 shows a block diagram of an example wireless communication device500. In some implementations, the wireless communication device 500 canbe an example of a device for use in a STA such as one of the STAs 104described above with reference to FIG. 1. In some implementations, thewireless communication device 500 can be an example of a device for usein an AP such as the AP 102 described above with reference to FIG. 1.The wireless communication device 500 is capable of transmitting andreceiving wireless communications in the form of, for example, wirelesspackets. For example, the wireless communication device can beconfigured to transmit and receive packets in the form of physical layerconvergence protocol (PLCP) protocol data units (PPDUs) and mediumaccess control (MAC) protocol data units (MPDUs) conforming to an IEEE802.11 wireless communication protocol standard, such as that defined bythe IEEE 802.11-2016 specification or amendments thereof including, butnot limited to, 802.11ay, 802.11ax, 802.11az, 802.11ba and 802.11be.

The wireless communication device 500 can be, or can include, a chip,system on chip (SoC), chipset, package or device that includes one ormore modems 502, for example, a Wi-Fi (IEEE 802.11 compliant) modem. Insome implementations, the one or more modems 502 (collectively “themodem 502”) additionally include a WWAN modem (for example, a 3GPP 4GLTE or 5G compliant modem). In some implementations, the wirelesscommunication device 500 also includes one or more processors,processing blocks or processing elements 504 (collectively “theprocessor 504”) coupled with the modem 502. In some implementations, thewireless communication device 500 additionally includes one or moreradios 506 (collectively “the radio 506”) coupled with the modem 502. Insome implementations, the wireless communication device 500 furtherincludes one or more memory blocks or elements 508 (collectively “thememory 508”) coupled with the processor 504 or the modem 502.

The modem 502 can include an intelligent hardware block or device suchas, for example, an application-specific integrated circuit (ASIC) amongother possibilities. The modem 502 is generally configured to implementa PHY layer, and in some implementations, also a portion of a MAC layer(for example, a hardware portion of the MAC layer). For example, themodem 502 is configured to modulate packets and to output the modulatedpackets to the radio 504 for transmission over the wireless medium. Themodem 502 is similarly configured to obtain modulated packets receivedby the radio 504 and to demodulate the packets to provide demodulatedpackets. In addition to a modulator and a demodulator, the modem 502 mayfurther include digital signal processing (DSP) circuitry, automaticgain control (AGC) circuitry, a coder, a decoder, a multiplexer and ademultiplexer. For example, while in a transmission mode, data obtainedfrom the processor 506 may be provided to an encoder, which encodes thedata to provide coded bits. The coded bits may then be mapped to anumber N_(SS) of spatial streams for spatial multiplexing or a numberN_(STS) of space-time streams for space-time block coding (STBC). Thecoded bits in the streams may then be mapped to points in a modulationconstellation (using a selected MCS) to provide modulated symbols. Themodulated symbols in the respective spatial or space-time streams may bemultiplexed, transformed via an inverse fast Fourier transform (IFFT)block, and subsequently provided to the DSP circuitry (for example, forTx windowing and filtering). The digital signals may then be provided toa digital-to-analog converter (DAC). The resultant analog signals maythen be provided to a frequency upconverter, and ultimately, the radio504. In implementations involving beamforming, the modulated symbols inthe respective spatial streams are precoded via a steering matrix priorto their provision to the IFFT block.

While in a reception mode, the DSP circuitry is configured to acquire asignal including modulated symbols received from the radio 504, forexample, by detecting the presence of the signal and estimating theinitial timing and frequency offsets. The DSP circuitry is furtherconfigured to digitally condition the signal, for example, using channel(narrowband) filtering and analog impairment conditioning (such ascorrecting for I/Q imbalance), and by applying digital gain toultimately obtain a narrowband signal. The output of the DSP circuitrymay then be fed to the AGC, which is configured to use informationextracted from the digital signals, for example, in one or more receivedtraining fields, to determine an appropriate gain. The output of the DSPcircuitry also is coupled with a demultiplexer that demultiplexes themodulated symbols when multiple spatial streams or space-time streamsare received. The demultiplexed symbols may be provided to ademodulator, which is configured to extract the symbols from the signaland, for example, compute the logarithm likelihood ratios (LLRs) foreach bit position of each subcarrier in each spatial stream. Thedemodulator is coupled with the decoder, which may be configured toprocess the LLRs to provide decoded bits. The decoded bits may then bedescrambled and provided to the MAC layer (the processor 506) forprocessing, evaluation or interpretation.

The radio 504 generally includes at least one radio frequency (RF)transmitter (or “transmitter chain”) and at least one RF receiver (or“receiver chain”), which may be combined into one or more transceivers.For example, each of the RF transmitters and receivers may includevarious analog circuitry including at least one power amplifier (PA) andat least one low-noise amplifier (LNA), respectively. The RFtransmitters and receivers may, in turn, be coupled to one or moreantennas. For example, in some implementations, the wirelesscommunication device 500 can include, or be coupled with, multipletransmit antennas (each with a corresponding transmit chain) andmultiple receive antennas (each with a corresponding receive chain). Thesymbols output from the modem 502 are provided to the radio 504, whichthen transmits the symbols via the coupled antennas. Similarly, symbolsreceived via the antennas are obtained by the radio 504, which thenprovides the symbols to the modem 502.

The processor 506 can include an intelligent hardware block or devicesuch as, for example, a processing core, a processing block, a centralprocessing unit (CPU), a microprocessor, a microcontroller, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a programmable logic device (PLD) such as a field programmablegate array (FPGA), discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. The processor 506 processes information receivedthrough the radio 504 and the modem 502, and processes information to beoutput through the modem 502 and the radio 504 for transmission throughthe wireless medium. For example, the processor 506 may implement acontrol plane and at least a portion of a MAC layer configured toperform various operations related to the generation, transmission,reception and processing of MPDUs, frames or packets. In someimplementations, the MAC layer is configured to generate MPDUs forprovision to the PHY layer for coding, and to receive decodedinformation bits from the PHY layer for processing as MPDUs. The MAClayer may further be configured to allocate time and frequencyresources, for example, for OFDMA, among other operations or techniques.In some implementations, the processor 506 may generally control themodem 502 to cause the modem to perform various operations describedabove.

The memory 504 can include tangible storage media such as random-accessmemory (RAM) or read-only memory (ROM), or combinations thereof. Thememory 504 also can store non-transitory processor- orcomputer-executable software (SW) code containing instructions that,when executed by the processor 506, cause the processor to performvarious operations described herein for wireless communication,including the generation, transmission, reception and interpretation ofMPDUs, frames or packets. For example, various functions of componentsdisclosed herein, or various blocks or steps of a method, operation,process or algorithm disclosed herein, can be implemented as one or moremodules of one or more computer programs.

FIG. 6A shows a block diagram of an example AP 602. For example, the AP602 can be an example implementation of the AP 102 described withreference to FIG. 1. The AP 602 includes a wireless communication device(WCD) 610 (although the AP 602 may itself also be referred to generallyas a wireless communication device as used herein). For example, thewireless communication device 610 may be an example implementation ofthe wireless communication device 5000 described with reference to FIG.5. The AP 602 also includes multiple antennas 620 coupled with thewireless communication device 610 to transmit and receive wirelesscommunications. In some implementations, the AP 602 additionallyincludes an application processor 630 coupled with the wirelesscommunication device 610, and a memory 640 coupled with the applicationprocessor 630. The AP 602 further includes at least one external networkinterface 650 that enables the AP 602 to communicate with a core networkor backhaul network to gain access to external networks including theInternet. For example, the external network interface 650 may includeone or both of a wired (for example, Ethernet) network interface and awireless network interface (such as a WWAN interface). Ones of theaforementioned components can communicate with other ones of thecomponents directly or indirectly, over at least one bus. The AP 602further includes a housing that encompasses the wireless communicationdevice 610, the application processor 630, the memory 640, and at leastportions of the antennas 620 and external network interface 650.

FIG. 6B shows a block diagram of an example STA 604. For example, theSTA 604 can be an example implementation of the STA 104 described withreference to FIG. 1. The STA 604 includes a wireless communicationdevice 615 (although the STA 604 may itself also be referred togenerally as a wireless communication device as used herein). Forexample, the wireless communication device 615 may be an exampleimplementation of the wireless communication device 500 described withreference to FIG. 5. The STA 604 also includes one or more antennas 625coupled with the wireless communication device 615 to transmit andreceive wireless communications. The STA 604 additionally includes anapplication processor 635 coupled with the wireless communication device615, and a memory 645 coupled with the application processor 635. Insome implementations, the STA 604 further includes a user interface (UI)655 (such as a touchscreen or keypad) and a display 665, which may beintegrated with the UI 655 to form a touchscreen display. In someimplementations, the STA 604 may further include one or more sensors 675such as, for example, one or more inertial sensors, accelerometers,temperature sensors, pressure sensors, or altitude sensors. Ones of theaforementioned components can communicate with other ones of thecomponents directly or indirectly, over at least one bus. The STA 604further includes a housing that encompasses the wireless communicationdevice 615, the application processor 635, the memory 645, and at leastportions of the antennas 625, UI 655, and display 665.

In addition to participating in a WLAN, STAs may also participate in apeer-to-peer (P2P), ad hoc or mesh network. In such instances, STAs cancommunicate directly with each other via P2P wireless links without theuse of an intermediary AP. In some deployments, regular infrastructuretraffic to and from an AP and an associated set of STAs may interferewith P2P traffic among the STAs, or vice versa. Techniques for achievingcoexistence are desired.

Recent wireless communication protocols, including IEEE 802.11be, maysupport scheduled access techniques in addition to, or as an alternativeto, conventional DCF and EDCA techniques, enabling multiple APs and STAsto share and communicate over a wireless medium. Such wirelesscommunication protocols may additionally or alternatively support theuse of time and frequency resource sharing within a transmissionopportunity.

Various aspects of the techniques, methods and devices disclosed hereinrelate generally to achieving coexistence between WLAN and peer-to-peer(P2P) or ad hoc networks, and specifically, to coordinateddevice-to-device (D2D) communications. Some aspects (described withreference to FIGS. 7-9, 18 and 19) particularly involve extending thecapabilities of target wake time (TWT) elements transmitted by wirelessaccess points to support periodic reserved access windows during whichD2D-enabled wireless devices are permitted to transmit direct wirelesscommunications to other D2D-enabled wireless devices.

Some other aspects (described with reference to FIGS. 10-14 and 20-22)relate to sharing time and frequency resources of a wireless medium, andmore particularly, coordinated access point (CAP)time-division-multiple-access (TDMA) or CAPorthogonal-frequency-division-multiple-access (OFDMA) techniques forsharing the time and frequency resources of a transmission opportunity.According to such techniques, a wireless access point that winscontention and gains access to the wireless medium for the duration of aTXOP may share its time and frequency resources with other coordinatedaccess points. The coordinated access points may then specificallyallocate at least some of the time and frequency resources in theirrespective time and frequency resources specifically for D2Dcommunications.

In some other aspects (described with reference to FIGS. 15-17, 23 and24), a D2D-enabled wireless device may form or join a P2P network thatalso includes a first set of other D2D-enabled wireless devices. TheD2D-enabled wireless device may receive a first indication from awireless access point that indicates periodic coordinated access windowsduring which wireless access points are scheduled to contend for accessand during which the set of D2D-enables wireless devices are notpermitted to contend for access. The D2D-enabled wireless device mayalso receive a second indication of a reserved access window within oneor more of the periodic coordinated access windows during which at leastsome of the set of D2D-enabled wireless devices are permitted totransmit direct wireless communications to other D2D-enabled wirelessdevices network despite the permissions associated with the firstindication.

FIG. 7 shows a flowchart illustrating an example process 700 forwireless communication that supports coordinated D2D communicationsaccording to some implementations. The operations of the process 700 maybe implemented by a wireless access point or its components as describedherein. For example, the process 700 may be performed by a wirelesscommunication device such as the wireless communication device 500described above with reference to FIG. 5. In some implementations, theprocess 700 may be performed by a wireless access point, such as one ofthe APs 102 and 602 described above with reference to FIGS. 1 and 6A,respectively.

In block 702, the wireless communication device (hereinafter referred toas the first wireless access point with respect to FIG. 7) transmits afirst wireless packet to at least a first set of wireless stations in afirst BSS controlled by the first wireless access point. Each wirelessstation in the first set of wireless stations is also configured for D2Dcommunications (also referred to generally herein as direct wirelesscommunications) with other wireless stations. In some implementations,the first wireless packet includes an indication of periodic reservedaccess windows. The indication of the periodic reserved access windowsindicates to the first set of wireless stations that they are permittedto transmit direct wireless communications to other wireless stations inthe first set of wireless stations on one or more wireless channels. Insome implementations, in block 704, the first wireless access pointrefrains from transmitting wireless communications during the periodicreserved access windows.

FIG. 8 shows a timing diagram illustrating example periodic reservedaccess windows 802 that support coordinated D2D communications accordingto some implementations. For example, the periodic reserved accesswindows 802 are examples of the periodic reserved access windowsdescribed with reference to the process 700. The periodic reservedaccess windows 802 recur according to a time interval τ_(Res) that maybe synchronized with the transmissions of beacon frames 806 by the firstwireless access point according to a beacon interval τ_(Beacon).

In some implementations, the first set of wireless stations are notpermitted to transmit direct wireless data communications to otherwireless stations outside of periodic reserved access windows 802 (butthey may be able to transmit other direct non-data wirelesscommunications in, for example, discovery windows outside of thereserved access windows). In some implementations, the indication of theperiodic reserved access windows 802 indicates to the first set ofwireless stations that they are permitted to transmit direct wirelesscommunications to other wireless stations outside of the first set ofwireless stations (for example, in other BSSs managed by other wirelessaccess points) during at least a portion of one or more of the periodicreserved access windows 802. In some implementations, the indication ofthe periodic reserved access windows 802 indicates to other wirelessstations in other BSSs that they are permitted to transmit directwireless communications to other wireless stations, which may includethe first set of wireless stations, on the one or more wireless channelsduring at least a portion of one or more of the reserved access windows802.

In some implementations, the first wireless access point transmits awireless packet such as the first wireless packet periodically. Forexample, each of the first wireless packet and the other periodicwireless packets may include a beacon frame such as one of the beaconframes 806. In some such implementations, each of the beacon framesincludes one or more target wake time (TWT) information elements (IEs).Each TWT IE includes an indication of a schedule of wake periods for oneor more wireless stations in the first BSS. For example, each TWT IE maybe an individual TWT addressed to a single wireless station, or abroadcast TWT addressed to a set of wireless stations such as the firstset of wireless stations. During each wake period, the wireless stationor set of wireless stations identified in the respective TWT are to beawake to receive wireless communications from the first wireless accesspoint. The identified wireless stations may also contend for access tothe wireless medium during the respective wake periods in someimplementations. In some implementations, at least one of the TWT IEsincludes the indication of the periodic reserved access windows 802. Forexample, the indication of the periodic reserved access windows 802 mayinclude an indication that each of the wake periods in the respectiveschedule of wake periods is a reserved access window 802. In some otherimplementations, the first wireless packet may be another type of frame,for example, another management frame such as a probe response framethat includes the indication of the periodic reserved access windows802.

In some implementations, the process 700 further includes exchanging oneor more wireless packets with one or more other wireless access pointsto coordinate a schedule of the periodic reserved access windows 802.For example, the exchange of the one or more wireless packets mayinclude transmitting beacons and receiving beacons from the otherwireless access points that each include timing information forcoordinating the schedule of the periodic reserved access windows 802.

In some implementations, the TWT IE indicating the periodic reservedaccess windows 802 includes one or more other parameters for theperiodic reserved access windows 802. In some implementations, the oneor more other parameters include a time slot schedule defining a seriesof time slots in the periodic reserved access windows 802. For example,FIG. 8 shows an implementation in which each of the reserved accesswindows 802 is divided into a number of time slots 804. In someimplementations, each of the time slots 804 may be separated from eachother time slot 804 by an interframe space (IFS), for example, a shortinterframe space (SIFS). In the illustrated example, each of thereserved access windows 802 includes four time slots 804 ₁-804 ₄,although the number of time slots may be more or less than four, and maybe adjusted or distributed differently in different reserved accesswindows. In some such implementations, the process 700 further includesallocating each of one or more of the time slots 804 to a respectivesubset of the first set of wireless stations (for example, two or morewireless stations) for the direct wireless communications. For example,each subset of wireless stations in the first set of wireless stationsmay not be permitted to transmit direct wireless communications inanother time slot allocated to a different subset of wireless stationsin the first set of wireless stations.

In some implementations, during at least one of the time slots 804, atleast some of the first set of wireless stations may be permitted totransmit or receive direct wireless communications to or from otherwireless stations associated with other BSSs controlled by other accesspoints. In some such implementations, the first wireless access pointand other wireless access points may not restrict direct wirelesscommunications to any individual BSS in at least one of the time slots804. Additionally or alternatively, the first wireless access point andthe other wireless access points may exchange one or more wirelesspackets to further coordinate a time slot schedule for the time slots804 within at least one of the reserved access windows 802. In some suchimplementations, the exchange includes transmitting, to at least one ofthe wireless access points, identifiers of one or more wireless stationsin the first set of wireless stations. The exchange further includesreceiving, from the wireless access point, identifiers of one or morewireless stations associated with the wireless access point that areconfigured for direct wireless communications with other wirelessstations. The two wireless access points may coordinate which wirelessstations of the first set of wireless stations are permitted to transmitdirect wireless communications to wireless stations associated with theother wireless access point during one or more time slots 804 allocatedto the other wireless access point. Similarly, the coordination mayinclude determining which wireless stations of the set of wirelessstations associated with the other wireless access point are permittedto transmit direct wireless communications to wireless stations in thefirst set of wireless stations during one or more time slots 804allocated to the first set of wireless stations.

In some implementations, for example, simplex implementations, wirelessstations that receive direct wireless communications from other wirelessstations in a respective time slot 804 are permitted to transmit anacknowledgment during a next time slot 804 in the respective reservedaccess window that acknowledges a direct wireless communicationtransmitted in the respective time slot 804.

In some implementations, the one or more other parameters identified inthe indication of the periodic reserved access window 802 may furtherinclude a frame type for direct wireless communication permitted to betransmitted during the periodic reserved access windows 802 or any othercontrol information for controlling direct wireless communication duringthe reserved access windows 802.

In some implementations, the process 700 further includes transmitting atrigger frame to the first set of wireless stations at a beginning of areserved access window 802 that triggers or initiates direct wirelesscommunications by the wireless stations in the first set of wirelessstations. For example, the trigger frame may indicate to the first setof wireless stations that they are permitted to contend for accessduring respective slots within the reserved access window 802. In someother implementations, the process 700 may further include transmittinga reverse direction grant (RDG) to one or more of the wireless stationsin the first set of wireless stations to initiate the direct wirelesscommunications with other wireless stations.

As described above, in some implementations, for example, to reducecongestion caused by direct wireless communications outside of thereserved access windows 802, the first wireless access point mayinstruct the first set of wireless stations to not transmit directwireless communications (except for direct wireless communicationsduring discovery windows) outside of the periodic reserved accesswindows 802. In some such implementations, the first wireless packet oranother wireless packet may include one or more quiet elements. Eachquiet element may indicate to any wireless stations within range,including the first set of wireless stations, that they are notpermitted to transmit on the one or more wireless channels during quietperiods associated with the quiet elements. For example, each quietelement may include multiple fields including an element identification(ID), a length, a quiet count, a quiet period, a quiet duration and aquiet offset as, for example, defined in the IEEE 802.11 specification.Additionally or alternatively, to reduce congestion caused by directwireless communications outside of the reserved access windows 802, thefirst wireless access point may include an indication in the firstwireless packet to the first set of wireless stations to follow one ormore multi-user (MU) enhanced distributed channel access (EDCA)parameters outside of the periodic reserved access windows 802.

In some implementations, the first set of wireless stations may beenabled for NAN operation and the direct wireless communications mayinclude NAN communications. In some such implementations, the firstwireless access point may permit only the wireless stations in the NANnetwork to access the one or more wireless channels in the periodicreserved access windows 802. For example, the indication of the periodicreserved access windows 802 transmitted in block 702 may include anindication of a NAN cluster ID identifying the wireless stations thatare allocated access to the one or more wireless channels during thereserved access windows 802. In some implementations, the first set ofwireless stations may not be permitted to transmit direct wirelesscommunications to other wireless stations outside of the periodicreserved access windows 802 except for direct wireless communications inNAN discovery windows (that is, direct wireless data communications arenot permitted outside of the periodic reserved access windows 802). Thefirst set of wireless stations may operate a NAN network alone or incombination with other NAN-enabled wireless stations, which may beassociated with other BSSs controlled by other wireless access points.

In some such implementations, the process 700 may further includereceiving, from at least one wireless station in the first set ofwireless stations, a wireless packet including an action frame thatindicates one or more parameters associated with the NAN networkincluding a timing of a periodic NAN discovery window. In some otherimplementations, the process 700 may further include scanning one ormore NAN discovery channels and determining that the first set ofwireless stations is operating a NAN network. The first wireless accesspoint may then identify one or more parameters associated with the NANnetwork including a timing of a NAN discovery window.

In some such implementations, the first wireless access point maytransmit a wireless packet to each of one or more other wireless accesspoints that includes an indication of the one or more parametersassociated with the NAN network. The first wireless access point and theother wireless access points may then schedule the periodic reservedaccess windows 802 based on the one or more parameters associated withthe NAN network including the timing of the NAN discovery window. Insome such implementations, the scheduling of the periodic reservedaccess windows 802 includes synchronizing the periodic reserved accesswindows with the periodic NAN discovery windows.

FIG. 9 shows a flowchart illustrating an example process 900 forwireless communication that supports coordinated D2D communicationsaccording to some implementations. The operations of the process 900 maybe implemented by a wireless station or its components as describedherein. For example, the process 900 may be performed by a wirelesscommunication device such as the wireless communication device 500described above with reference to FIG. 5. In some implementations, theprocess 900 may be performed by a wireless communication deviceoperating as or within a wireless station, such as one of the STAs 104and 604 described above with reference to FIGS. 1 and 6B, respectively.

In block 902, the wireless communication device (hereinafter referred toas the first wireless station with respect to FIG. 9) receives a firstwireless packet from a first wireless access point that controls a firstBSS including a first set of wireless stations that includes the firstwireless station. The first wireless station is also configured fordirect (D2D) wireless communications with other wireless stations. Thefirst wireless packet includes an indication of periodic reserved accesswindows 802 during which the first wireless station is permitted totransmit direct wireless communications to one or more other wirelessstations in the first set of wireless stations on one or more wirelesschannels. In block 904, the first wireless station transmits a secondwireless packet directly to another wireless station during at least oneof the periodic reserved access windows 802.

As described above with reference to the process 700 of FIG. 7, in someimplementations, the first set of wireless stations, including the firstwireless station, are not permitted to transmit direct wireless datacommunications to other wireless stations outside of the periodicreserved access windows 802 (but they may be able to transmit otherdirect non-data wireless communications in, for example, discoverywindows outside of the reserved access windows 802). In someimplementations, the indication of the periodic reserved access windows802 indicates to the first set of wireless stations that they arepermitted to transmit direct wireless communications to other wirelessstations outside of the first set of wireless stations (for example, inother BSSs managed by other wireless access points) during at least aportion of one or more of the periodic reserved access windows 802. Insome implementations, the indication of the periodic reserved accesswindows 802 indicates to other wireless stations in other BSSs that theyare permitted to transmit direct wireless communications to otherwireless stations, which may include the first set of wireless stations,on the one or more wireless channels during at least a portion of one ormore of the reserved access windows 802.

As described above, in some implementations, the first wireless stationreceives a wireless packet such as the first wireless packetperiodically. For example, each of the first wireless packet and theother periodic wireless packets may include a beacon frame such as oneof the beacon frames 806. In some such implementations, each of thebeacon frames includes one or more TWT IEs. As described with referenceto the process 700 of FIG. 7, in some implementations, at least one ofthe TWT IEs includes the indication of the periodic reserved accesswindows 802. For example, the indication of the periodic reserved accesswindows 802 may include an indication that each of the wake periods inthe respective schedule of wake periods is a reserved access window 802.

In some implementations, the TWT IE indicating the periodic reservedaccess windows 802 includes one or more other parameters for theperiodic reserved access windows 802. As described above, in someimplementations, the one or more other parameters include a time slotschedule defining a series of time slots in the periodic reserved accesswindows 802. In some such implementations, the process 900 furtherincludes receiving an indication that at least one of the time slots isallocated to the first wireless station, or a group of wireless stationsin the first set of wireless stations that includes the first wirelessstation.

In some implementations, the one or more other parameters identified inthe indication of the periodic reserved access window 802 may furtherinclude a frame type for direct wireless communication permitted to betransmitted during the periodic reserved access windows 802 or any othercontrol information for controlling direct wireless communication duringthe reserved access windows 802.

In some implementations, the process 900 further includes receiving atrigger frame from the first wireless access point at a beginning of areserved access window 802 that triggers or initiates the first wirelessstation to transmit the second wireless packet in block 904. Forexample, the trigger frame may indicate to the first wireless stationthat it is permitted to contend for access during one or more slotswithin the reserved access window 802. In some other implementations,the process 900 further includes receiving an RDG frame from the firstwireless access point that triggers or initiates the first wirelessstation to transmit the second wireless packet in block 904.

In some implementations, the first set of wireless stations may beenabled for NAN operation and the direct wireless communications mayinclude NAN communications. In some such implementations, only wirelessstations in the NAN network are permitted to access the one or morewireless channels in the periodic reserved access windows 802. Forexample, the indication received in block 902 of the periodic reservedaccess windows 802 may include an indication of a NAN cluster IDidentifying the wireless stations that are allocated access to the oneor more wireless channels during the reserved access windows 802. Insome implementations, the first set of wireless stations may not bepermitted to transmit direct wireless communications to other wirelessstations outside of the periodic reserved access windows 802 except fordirect wireless communications in NAN discovery windows (that is, directwireless data communications are not permitted outside of the periodicreserved access windows 802). The first set of wireless stations mayoperate a NAN network alone or in combination with other NAN-enabledwireless stations, which may be associated with other BSSs controlled byother wireless access points.

In some implementations, the first wireless station may form or join aNAN network that includes the first set of wireless stations before theperformance of the process 900. In some such implementations, the firstwireless station transmits a wireless packet including an action frameto the first wireless access point that indicates one or more parametersassociated with the NAN network including a timing of a NAN discoverywindow. In some other implementations, the first wireless station mayperiodically broadcast wireless packets including action frames thatindicate the one or more parameters associated with the NAN networkincluding the timing of the NAN discovery window.

In some implementations, the first wireless station transmits a wirelesspacket to one or more wireless stations in the NAN network in each ofone or more of the NAN discovery windows that includes an indication ofthe periodic reserved access windows 802. In some implementations, thefirst wireless station exchanges one or more wireless packets with atleast one other wireless station in the NAN network to set up a NAN datalink (NDL) during at least one access window of the periodic reservedaccess windows 802. In such implementations, the first wireless stationtransmits the second wireless packet in block 904 directly to the otherwireless station via the NDL.

In some other implementations, the first wireless station may establisha tunneled direct link setup (TDLS) link with each of one or more otherwireless stations in the first set of wireless stations. In suchimplementations, the first wireless station may transmit the secondwireless packet directly to the other wireless station via the TDLSlink.

Various other aspects relate generally to sharing time or frequencyresources of a wireless medium. Particular implementations relate morespecifically to coordinated AP (CAP) time-division-multiple-access(TDMA) or CAP orthogonal-frequency-division-multiple-access (OFDMA)techniques for sharing the time and frequency resources of atransmission opportunity. According to such techniques, a wirelessaccess point that wins contention and gains access to the wirelessmedium for the duration of a TXOP may share its time and frequencyresources with other coordinated access points. To share its timeresources, the winning access point may partition the TXOP into multipleTXOP segments or bandwidth segments. For example, the winning accesspoint may assign, grant or allocate (hereinafter used interchangeably)itself one or more of the time segments and bandwidth segments and alsoallocate each of one or more remaining time or frequency segments to oneor more other ones of the coordinated access points. In someimplementations, the wireless access points may further allocate atleast some of the time and frequency resources in their respective timeand bandwidth segments specifically for D2D communications.

FIG. 10 shows a flowchart illustrating an example process 1000 forwireless communication that supports coordinated D2D communicationsaccording to some implementations. The operations of the process 1000may be implemented by a wireless access point or its components asdescribed herein. For example, the process 1000 may be performed by awireless communication device such as the wireless communication device500 described above with reference to FIG. 5. In some implementations,the process 1000 may be performed by a wireless access point, such asone of the APs 102 and 602 described above with reference to FIGS. 1 and6A, respectively.

In block 1002, the wireless communication device (hereinafter referredto as the first wireless access point or TXOP owner with respect to FIG.10) obtains a TXOP for wireless communication via one or more wirelesschannels. In block 1004, the first wireless access point selects one ormore other wireless access points to participate in the TXOP. In block1006, the first wireless access point allocates a respective set of timeand frequency resources of multiple sets of time and frequency resourcesof the TXOP to each of itself and the selected wireless access points.In block 1008, the first wireless access point allocates a first subsetof time and frequency resources, of the set of time and frequencyresources allocated to the first wireless access point, to a first setof wireless stations in a first BSS controlled by the first wirelessaccess point for direct (D2D) wireless communications with otherwireless stations. In block 1010, the first wireless access pointtransmits a first wireless packet to the one or more selected wirelessaccess points that includes, for each of the selected wireless accesspoints, an indication of the set of time and frequency resourcesallocated to the respective wireless access point. In block 1012, thefirst wireless access point transmits a second wireless packet to thefirst set of wireless stations that includes an indication of the firstsubset of time and frequency resources. In block 1014, the firstwireless access point refrains from transmitting wireless communicationsin the first subset of time and frequency resources.

FIG. 11 shows a timing diagram illustrating example reserved timeresources that support coordinated D2D communications according to someimplementations. For example, the first wireless access point andneighboring access points may be configured for coordinated access point(CAP) TDMA. The first wireless access point (API) obtains a TXOP 1102 inblock 1002 and shares it with one or multiple other coordinated accesspoints (for example, AP2 and AP3) using TDMA. As illustrated in FIG. 11,in some implementations, the TXOP 1102 includes multiple phase or stagesincluding a first TXOP indication phase 1104, a second scheduleallocation phase 1106, and a third data transmission phase 1108.

In some implementations, to obtain the TXOP 1102 in block 1002, thefirst wireless access point contends for access to the wireless mediumon one or more channels including a primary operating channel (forexample, a primary 20 MHz channel and one or more secondary 20 MHz, 40MHz, 80 MHz or 160 MHz channels) using, for example, CSMA/CA andenhanced distributed channel access (EDCA) techniques. The TXOP 1102 maybe obtained at time to for a wideband wireless channel, such as a bondedchannel formed by the primary channel and the one or more secondarychannels. For example, the wideband wireless channel may be a 40 MHz, 80MHz, 160 MHz or 320 MHz channel.

In some implementations, after obtaining the TXOP 1102, and to ensureinterference-free communications during the TXOP 1102, the firstwireless access point may further reserve the wireless channel bytransmitting a request-to-send (RTS) frame (not shown) to one or more ofits associated wireless stations. The RTS frame is configured to causeat least one of the stations to transmit a clear-to-send (CTS) frame.Any other wireless communication devices, including the wireless accesspoints AP2 and AP3, and their associated wireless stations, that receiveeither or both of the RTS or CTS frames may set their respective NAVsfor a duration of time indicated in the RTS or CTS frames.

In some implementations, to select the one or more other coordinatedwireless access points to participate in the TXOP 1102 in block 1004,the first wireless access point performs a TXOP availability indicationprocess during the TXOP indication phase 1104 during which the firstwireless access point learns of the other access points' desires orintents to participate in the TXOP 1102. For example, the process 1000may further include, during the TXOP indication phase 1104, advertisingan availability of time resources in the TXOP 1102. Specifically, attime t₁, the first wireless access point transmits a CAP TXOP indication(CTI) frame 1110 to other wireless access points, for example, otheraccess points in its extended service set (ESS), that indicates that thetime resources of the TXOP 1102 can be shared by the first wirelessaccess point. For example, the first wireless access point may havepreviously become aware of the other neighboring access points in itsvicinity based on information in beacons or other management framesreceived from the other access points.

After transmitting the CTI frame 1110, the first wireless access pointmay receive, at time t₂, a CAP TXOP request (CTR) frame 1112 from eachof one or more candidate APs that indicates a desire by the respectiveaccess point to participate in the TXOP 1102. In the example illustratedin FIGS. 11, AP2 and AP3 are among the candidate APs that transmitrespective CTR frames 1112 ₂ and 1112 ₃ to the first wireless accesspoint. Based on the receipt of the CTR frames 1112, the first wirelessaccess point may then select one or more of the candidate APs toparticipate in the TXOP 1102.

In some implementations, the CTI frame 1110 includes at least onetrigger frame configured to trigger the one or more candidate accesspoints to transmit the respective CTR frames 1112. To transmit the CTIframe 1110, the first wireless access point may transmit a PPDU thatincludes a same CTI trigger frame in each of multiple subchannels of thewireless channel (for example, in each of multiple 20 MHz channels). Forexample, the CTI frame 1110 may include a non-high-throughput (non-HT)duplicate trigger frame in each 20 MHz channel. In this way, the otheraccess points do not need to be operating on the same primary 20 MHzchannel to receive and process the CTI frame 1110. In someimplementations, a source address field and a BSSID field (for example,in a MAC header) associated with the CTI frame 1110 are set to the MACaddress of the first wireless access point and a destination addressfield (for example, in the MAC header) associated with the CTI frame1110 is set to a broadcast address.

Each duplicate trigger frame of the CTI frame 1110 may include, for eachof the multiple access points that may participate in the TXOP 1102, anindication of one or both of frequency resources or spatial resourcesusable by the respective access point to transmit its respective CTRframe 1112. For example, each trigger frame of the CTI frame 1110 mayinclude a user information field for each of the access points thatincludes the respective indication of the frequency resources or thespatial resources the access point is to use to transmit its CTR frame1112. Each user information field may include a respective AP identifier(APID) of the respective access point. For example, the APID may be aMAC address of the access point, a BSSID associated with the accesspoint or a BSS color associated with the access point. In some otherimplementations in which the first wireless access point may not beaware of some or all of the neighboring access points, the CTI frame1110 may include an indication of random access resources usable by theaccess points to transmit their respective CTR frames 1112.

The CTR frames 1112 may be received from the candidate access points inrespective trigger-based PPDUs in response to the CTI frame 1110 usingthe frequency or spatial resources allocated by the CTI frame 1110. Forexample, the CTR frames 1112 may be transmitted via MU OFDMA or MU MIMOtechniques and may be received at time t₄ a SIFS duration after the CTIframe 1110. Notably, for the access points capable of CAP TDMA, the CTIframe 1110 is configured to cause the access points to respond withrespective CTR frames 1112 regardless of their respective NAVs.

In some implementations, the first wireless access point may transmitmultiple CTI frames 1110, each to a respective one of the access points,on an AP-by-AP sequential basis. An access point desiring to participatein the TXOP 1102 may transmit, in response to receiving a respective oneof the CTI frames 1110, a CTR frame 1112 before the transmission of anext CTI frame 1110 to a next one of the APs. For example, each CTIframe 1110 may be a poll frame and each CTR frame 1112 may be a pollresponse frame. Such CTI frames 1110 and CTR frames 1112 may betransmitted as single-user (SU) transmissions. In some otherimplementations, the first wireless access point may transmit a singleCTI frame 1110, and subsequently, transmit a polling frame (poll) toeach of the access points, on an AP-by-AP sequential basis, thatsolicits a response CTR frame 1112 from the respective access pointbefore the transmission of a poll to a next one of the access points.

In some implementations, each of the CTR frames 1112 may include anindication of a buffer status of the respective AP or a duration of timeresources requested by the respective AP. In some such implementations,the first wireless access point may select the candidate access pointsto participate in the TXOP 1102 in block 1004 based on the indicationsof the buffer statuses or the desired durations of time resourcesreceived in the CTR frames 1112.

As described above, in block 1006, the first wireless access point mayallocate a respective set of time and frequency resources of the TXOP1102 to itself and to each of the selected access points. In someimplementations, the frequency resources in each set of time andfrequency resources overlap entirely throughout the bandwidth while thetime resources do not overlap at all for the duration of the TXOP 1202.In some other implementations or instances, the frequency resources mayalso not overlap in at least some portions of the bandwidth. As such, insome implementations, the first wireless access point may furtherallocate different frequency resources in addition to different timeresources.

For example, the first wireless access point may divide the availabletime resources of the TXOP 1102 into multiple time segments 1120, eachcomprising one or more time resources for itself or one of the selectedaccess points, and each not overlapping with any of the other timesegments 1120. For example, each of the time segments may include one ormore symbols or time slots or other time units. In some implementations,the first wireless access point divides the TXOP 1102 into equal timesegments 1120, where the number of equal time segments 1120 is equal tothe number of access points sharing the TXOP 1102. For example, asillustrated in FIG. 11, the first wireless access point may partitionthe TXOP 1102 into three equal time segments 1120, one time segment 1120₁ for the first wireless access point, one time segment 1120 ₂ for theselected access point AP2, and one time segment 1120 ₃ for the thirdaccess point AP3. In some other implementations or instances, the firstwireless access point may partition the time resources into unequal timesegments 1120. For example, the first wireless access point may selectfor itself a longer time segment 1120 ₁ of the TXOP 1102 including moretime resources than that in the other time segments 1120 allocated tothe other selected access points. In some implementations in which theCTR frames 1112 include indications of buffer statuses or desireddurations of time resources, the first wireless access point may basethe allocations of the time resources to the selected access pointsbased on their respective buffer statuses or requested time resources.

As described above, in block 1008, the first wireless access point mayallocate a subset of time and frequency resources of the TXOP 1102 to atleast a first set of wireless stations in the BSS controlled by thefirst wireless access point for direct wireless communications. Forexample, in some implementations, the first wireless access pointpartitions the available time resources of the time segment 1120 ₁ intomultiple portions including a portion 1122 ₁ it reserves for regularinfrastructure BSS traffic from itself to the first set of wirelessstations or from the first set of wireless stations to itself. The timesegment 1120 ₁ further includes a portion, including the subset of timeresources, that may be reserved for direct wireless communicationsbetween the first set of wireless stations or other wireless stationsassociated with other BSSs. In some implementations, the first set ofwireless stations are not permitted to transmit direct wireless datacommunications to other wireless stations outside of the subset of timeand frequency resources reserved for direct wireless communications.

In some implementations, the first wireless access point divides theportion reserved for the direct wireless communications into one ormultiple time slots 1124 ₁, each comprising one or more time resources.For example, each of the time slots may represent one symbol, multiplesymbols, or other time units. In some implementations, each of the timeslots 1124 ₁ may be separated from each other time slot 1124 ₁ by anIFS, for example, a SIFS. In some implementations, the first wirelessaccess point divides the portion reserved for the direct wirelesscommunications into equal length time slots 1124 ₁. In some otherimplementations or instances, the first wireless access point maypartition the time resources into unequal time slots 1124. In theillustrated example, the time segment 1120 ₁ includes three time slots1124 _(1A), 1124 _(2B) and 1124 _(3C), although the number of time slotsmay be more or less than three, and may be adjusted or distributeddifferently in different time segments 1120 within the same TXOP 1102 orsubsequent TXOPs 1102.

In some such implementations, block 1008 of the process 1000 may furtherinclude allocating each of one or more of the time slots 1124 ₁ to arespective subset of the first set of wireless stations (for example,two or more wireless stations) for the direct wireless communications.For example, each subset of wireless stations in the first set ofwireless stations may not be permitted to transmit direct wirelesscommunications in another one of the time slots 1124 ₁ allocated to adifferent subset of wireless stations in the first set of wirelessstations. In some implementations, during at least one of the time slots1124 ₁, for example, a last time slot 1124 _(1C), at least some (or all)of the first set of wireless stations may be permitted to transmit orreceive direct wireless communications to or from other wirelessstations associated with other BSSs controlled by other access pointsincluding AP2 and AP3. In some such implementations, the first wirelessaccess point and other wireless access points may not restrict directwireless communications to any individual BSS in the time slot 1124_(1C).

Additionally or alternatively, the first wireless access point and theselected wireless access points including AP2 and AP3 may exchange oneor more wireless packets to further coordinate a time slot schedule forthe time slots 1124 in the time segments 1120. For example, the exchangemay include transmitting, to at least one of the selected access points,identifiers of one or more wireless stations in the first set ofwireless stations. For example, each of the wireless stations may beuniquely identified by a combination of BSS color and associatedidentifier (AID). The exchange may further include receiving, from thewireless access points, identifiers of one or more wireless stationsassociated with the wireless access point that are configured for directwireless communications with other wireless stations. The first wirelessaccess point and the other wireless access points may coordinate whichwireless stations of the first set of wireless stations are permitted totransmit direct wireless communications to wireless stations associatedwith the other wireless access point during one or more time slots, forexample, time slots 1124 ₂ and 1124 ₃ allocated to the other wirelessaccess points AP2 and AP3, respectively. Similarly, the coordination mayinclude determining which wireless stations of the set of wirelessstations associated with the other wireless access points are permittedto transmit direct wireless communications to wireless stations in thefirst set of wireless stations during one or more time slots of the timeslots 1124 ₁ allocated to the first set of wireless stations.

Similarly, each of the selected access points AP2 and AP3 may partitionits allocated time segment 1120 ₂ or 1120 ₃, respectively, into aportion 1122 ₂ or 1122 ₃, respectively, it reserves for regularinfrastructure BSS traffic with associated wireless stations in its BSS.As described above, each of the time segments 1120 ₂ and 1120 ₃ furtherincludes a portion, including a subset of time resources, that may bereserved for direct wireless communications between the respectivewireless stations or other wireless stations associated with other BSSsincluding the first set of wireless stations. As further describedabove, each of the access points AP2 and AP3 may divide the portionreserved for the direct wireless communications into one or multipletime slots 1124 ₂ or 1124 ₃, respectively, each comprising one or moretime resources. In some implementations, as described further below, thefirst wireless access point and the selected access points AP2 and AP3may be configured to synchronize the timing of at least overlapping onesof the time slots 1124 ₁, 1124 ₂ and 1124 ₃.

Each of the access points AP2 and AP3 may allocate each of one or moreof the time slots 1124 ₂ and 1124 ₃, respectively, to a respectivesubset of the wireless stations associated with the respective accesspoint for the direct wireless communications. In some implementations,at least some of the time slots 1124 may be coordinated or correspondwith each other. For example, during at least one of the time slots 1124₁, 1124 ₂ and 1124 ₃, for example, corresponding common time slots 1124_(1C), 1124 _(2B) and 1124 _(3A), respectively, in each of the timesegments 1120 ₁, 1120 ₂ and 1120 ₃, respectively, at least some (or all)of the wireless stations associated with the respective access pointsmay be permitted to transmit or receive direct wireless communicationsto or from other wireless stations associated with the other BSSscontrolled by the other access points. In some such implementations, thefirst wireless access point and the selected access points AP2 and AP3may not restrict direct wireless communications to any individual BSS inthe common time slot.

After selecting the access points to participate in the TXOP 1102 inblock 1004 and allocating the sets of time (and in some implementations,frequency) resources in blocks 1004 and 1006, the first wireless accesspoint then grants, schedules or otherwise actually allocates (forexample, indicates the allocations of) the respective time resources tothe selected access points in the schedule allocation phase 1106. Forexample, the first wireless access point may transmit, at time t₃, a CAPTXOP AP schedule (CTAS) frame 1114 that includes, for each of theselected access points, the indication of the time (and in someimplementations, frequency) resources allocated to the respective accesspoint and usable by the respective access point and its BSS to transmitdata to, or receive data from, one or more respective associatedwireless stations during the TXOP 1102. For example, the CTAS frame 1114may be transmitted at time t₃ a SIFS duration after the CTR frames 1112.In such implementations, the first wireless packet transmitted by thefirst wireless access point in block 1010 of the process 1000 includesthe CTAS frame 1114.

To transmit the CTAS frame 1114, the first wireless access point maytransmit a PPDU that includes a same CTAS trigger frame in each ofmultiple subchannels of the wireless channel (for example, in each ofmultiple 20 MHz channels). For example, the CTAS frame 1114 may includea non-HT duplicate trigger frame in each 20 MHz channel. In this way,the other access points do not need to be operating on the same primary20 MHz channel to receive and process the CTAS frame 1114. In someimplementations, a source address field and a BSSID field (for example,in a MAC header) associated with the CTAS frame 1114 are set to the MACaddress of the first wireless access point and a destination addressfield (for example, in the MAC header) associated with the CTAS frame1114 is set to a broadcast address.

Each duplicate trigger frame of the CTAS frame 1114 may include, foreach of the selected access points, an indication of the time resourcesallocated to the respective access point and its BSS. For example, eachtrigger frame of the CTAS frame 1114 may include a user informationfield for each of the selected access points. Each user informationfield may include a respective APID of a respective access point. Forexample, the APID may be a MAC address of the access point, a BSSIDassociated with the access point or a BSS color associated with theaccess point. Each user information field includes, for the respectiveaccess point, an indication of a starting time of the respectiveallocated time resources. For example, the user information field mayinclude an indication of a symbol, a time slot or an absolute orrelative time at which the allocated time resources begin. The userinformation field may also include a duration of the respectiveallocated time resources, for example, in units of symbols, time slotsor milliseconds (ms). In some implementations, the CTAS frame 1114further includes, for example, in one or more user information fields,an indication of a time slot schedule, and in some instances,identifiers of the wireless stations allocated use of the respectivetime slots. Each user information field may further include, for therespective selected access point, an indication of frequency resourcesavailable for use by the respective access point while using therespective allocated time resources. For example, the user informationfield may indicate one or more channels or subchannels (for example, oneor more 20 MHz channels) or one or more resource units (RUs) usable bythe respective access point and its BSS while using the allocated timeresources. As described elsewhere herein, in some implementations orinstances, the first wireless access point and one or more of AP2 andAP3 may be configured for communication via CAP TDMA as well as CAPOFDMA simultaneously. As described above, in other implementations orinstances, the CTAS frame 1114 may allocate all of the availablefrequency resources to each of the selected access points for use whileusing their respective allocated time resources.

After transmitting the CTAS frame 1114, the first wireless access point,at time t₄, transmits a CAP TXOP Local Schedule (CTLS) frame 1116 ₁ tothe first set of wireless stations in its BSS. Similarly, each of theselected access points AP2 and AP3 may also transmit respective CTLSframes 1116 ₂ and 1116 ₃, respectively, to the associated wirelessstations in their respective BSSs at time t₄. In some implementations,the CTAS frame 1114 includes at least one trigger frame configured totrigger the selected access points AP2 and AP3 to transmit therespective CTLS frames 1116 ₂ and 1116 ₃ to their associated BSSssimultaneously with the first wireless access point transmitting theCTLS frame 1116 ₁ to its associated BSS at time t₄, for example, a SIFSduration after the CTAS frame 1114. Each of the CTLS frames 1116 mayidentify the time (and frequency) resources allocated to the respectiveaccess point and its associated BSS, and may indicate that theidentified time resources are reserved for use by, or otherwiseallocated to, the respective BSS. Notably, for the access points capableof CAP TDMA, the CTAS frame 1114 is configured to cause the selectedaccess points to transmit the respective CTLS frames 1116 regardless oftheir respective NAVs.

In some implementations, the second wireless packet transmitted by thefirst wireless access point in block 1012 of the process 1000 includesthe CTLS frame 1116 ₁. In such implementations, the CTLS frame 1116 ₁includes an indication of the subset of time and frequency resourcesallocated to the first set of wireless stations, or other wirelessstations associated with other BSSs, for direct wireless communications.As described above, the indication may include, for each of one or morestations of the first set of wireless stations, an indication of one ormore particular time slots 1124 ₁ allocated to the respective wirelessstation for direct wireless communications. For example, in someimplementations, the CTLS frame 1116 ₁ includes a time slot schedulethat defines the time slots as well as identifiers (for example, basedon BSS color and AID) of the associated wireless stations allocated useof the respective time slots 1124 ₁. In some other implementations, thesecond wireless packet may include the indication of the subset of timeand frequency resources allocated for the direct wireless communicationsin another frame, and may be transmitted, for example, aftertransmitting a wireless packet including the CTLS frame 1216 ₁. In someimplementations, the CTLS frame 1116 ₁ or other frame may include one ormore other parameters for the time slots 1124 ₁ such as, for example, aframe type for direct wireless communication permitted to be transmittedduring the time slots 1124 ₁ or any other control information forcontrolling direct wireless communication during the time slots.

In some implementations, the CTLS frames 1116 transmitted by the firstwireless access point and the selected access points AP2 and AP3 arenon-HT duplicate frames. That is, in some implementations, each of theCTLS frames 1116 is identical to the others. Additionally, each of theCTLS frames 1116 transmitted by the first wireless access point and theselected access points may be transmitted simultaneously via all of theavailable frequency resources of the wireless channel. In this way, theCTLS frames 1116 will not destructively interfere with each other andthe stations receiving the CTLS frames 1116 may properly decode them. Insome implementations, a source address field (for example, in a MACheader) associated with each of the CTLS frames 1116 is set to the samemulticast address or other predefined address associated with CAP TDMAtransmissions. Wireless stations supporting CAP TDMA may be configuredsuch that when they receive frames having the multicast address, theydecode and parse the respective frames. In some implementations, a BSSIDfield (for example, in the MAC header) associated with each of the CTLSframes 1116 is set to the BSSID of the first wireless access point. Insome such implementations, a destination address field (for example, inthe MAC header) associated with each of the CTLS frames 1116 is set tothe same broadcast address.

In some implementations, each of the CTLS frames 1116 transmitted by thefirst wireless access point and the selected access points AP2 and AP3includes an information element (IE) for each of the access points AP1,AP2 and AP3 that includes, for the respective access point, anindication of the starting time of the respective allocated timeresources. For example, each IE may include an indication of a symbol, atime slot or an absolute or relative time at which the allocated timeresources begin. The IE may also include a duration of the respectiveallocated time resources, for example, in units of symbols, time slotsor ms. In some implementations, each of the CTLS frames 1116 furtherincludes, for example, in one or more IEs, an indication of the subsetof time and frequency resources allocated for direct wirelesscommunications. For example, an IE may include a time slot schedule andidentifiers of the wireless stations allocated use of the respectivetime slots. As described elsewhere herein, each IE may further includean indication of frequency resources (for example, one or more channels,subchannels or RUs) available for use while using the respectiveallocated time resources. Because the stations associated with theselected access points may not be in range of, or otherwise be able toreceive and process the CTAS frame 1114, the use of the CTLS frames 1116ensures that the stations become aware of the allocated time (andfrequency) resources.

After the access point and local scheduling during the scheduleallocation phase 1106, the data transmission phase 1108 may begin.During the data transmission phase 1108, the BSSs controlled by thefirst wireless access point and the selected access points AP2 and AP3may share the time and frequency resources of the TXOP 1102 as describedabove. For example, in the first portion 1122 ₁ of the first timesegment 1120 ₁, the first wireless access point may transmit downlink(DL) communications to, or receive uplink (UL) communications from, thefirst set of wireless stations using any of the single-user (SU) ormulti-user (MU) techniques (for example, MU MIMO or MU OFDMA) describedabove during the first portion 1122 ₁.

During the time slots 1124 ₁, the first set of wireless stations maytransmit or receive direct wireless communications to or from otherwireless stations within the BSS controlled by the first wireless accesspoint, and in some implementations or instances, to or from otherwireless stations associated with other BSSs, for example, controlled byaccess points AP2 and AP3. In some implementations, the first wirelessaccess point refrains from transmitting on the one or more wirelesschannels associated with the TXOP 1102 during the time slots 1124 ₁.However, as one exception, in some such implementations, the firstwireless access point may transmit a trigger frame at a beginning of oneor more of the time slots 1124 ₁ that initiates the direct wirelesscommunication by the wireless stations allocated use of the respectivetime slots 1124 ₁. For example, the trigger frame may indicate to thefirst set of wireless stations that they are permitted to contend foraccess during the respective slots 1124 ₁. In some other suchimplementations, the first wireless access point may transmit an RDGframe at a beginning of one or more of the time slots 1124 ₁ thatinitiates the direct wireless communication by the wireless stationsallocated use of the respective time slots 1124 ₁.

In some implementations, there may be a guard (or “non-transmission”)interval (for example, for a SIFS duration) between the time segments1120 allocated to the respective access points to buffer and guardagainst interference that may result from overlapping communicationsthat may result from timing errors.

To ensure that the first wireless access point and the selected accesspoints AP2 and AP3, or their respective wireless stations, transmit orreceive their respective data communications during only their allocatedtime resources (such that they don't interfere with one another), thefirst wireless access point may synchronize the selected access points,and in some instances, their respective wireless stations, in time. Forexample, in some implementations, in a beginning portion of the datatransmission phase 1108, the first wireless access point transmits atrigger frame (referred to herein as a CAP TXOP trigger (CTTRIG) frame)at time t₅ after the CTLS frames 1116 are transmitted to synchronize intime the selected access points with the first wireless access point. Insome implementations, data communications may begin a SIFS durationafter the CTTRIG frame. Notably, the access points capable of CAP TDMAare configured to transmit and receive data communications,acknowledgment (ACK) frames, and trigger frames regardless of theirrespective NAVs during their allocated time resources. Additionally, thewireless stations compatible with CAP TDMA may be configured to be in anactive listening mode at least during the respective allocated timeresources and such that they may transmit and receive datacommunications, ACK frames, and trigger frames regardless of theirrespective NAVs.

As described above, in some implementations, for example, simpleximplementations, wireless stations that receive direct wirelesscommunications from other wireless stations in a respective time slotare permitted to transmit an acknowledgment during a next time slot thatacknowledges a direct wireless communication transmitted in therespective time slot.

FIG. 12 shows a timing diagram illustrating example reserved frequencyresources that support coordinated D2D communications according to someimplementations. For example, the first wireless access point andneighboring access points may be configured for coordinated access point(CAP) OFDMA. Still referring back to the process 1000 described withreference to FIG. 10, the first wireless access point (AP1) obtains aTXOP 1202 in block 1002 and shares it with one or multiple othercoordinated access points (for example, AP2) using OFDMA. As illustratedin FIG. 12, in some implementations, the TXOP 1202 includes multiplephase or stages including a first TXOP indication phase 1204, a secondschedule allocation phase 1206, and a third data transmission phase1208.

As described above with reference to FIG. 11, to obtain the TXOP 1202 inblock 1002, the first wireless access point contends for access to thewireless medium on one or more channels using, for example, CSMA/CA andEDCA techniques. The TXOP 1202 may be obtained at time t₀ for a widebandwireless channel, such as a bonded channel formed by the primary channeland the one or more secondary channels. For example, the widebandwireless channel may be a 40 MHz, 80 MHz, 160 MHz or 320 MHz channel.After obtaining the TXOP 1202, and to ensure interference-freecommunications during the TXOP 1202, the first wireless access point mayfurther reserve the wireless channel by transmitting a RTS frame (notshown) to one or more of its associated wireless stations. The RTS frameis configured to cause at least one of the stations to transmit a CTSframe.

As described above with reference to FIG. 11, in some implementations,to select the one or more other coordinated wireless access points toparticipate in the TXOP 1202 in block 1004, the first wireless accesspoint performs a TXOP availability indication process in the TXOPindication phase 1204 during which the first wireless access pointlearns of the other access points' desires or intents to participate inthe TXOP 1202. For example, the process 1000 may further include, duringthe TXOP indication phase 1204, advertising an availability of frequencyresources in the TXOP 1202. Specifically, at time t₁, the first wirelessaccess point transmits a CTI frame 1210 to other wireless access points,for example, other access points in its ESS, that indicates that thefrequency resources of the TXOP 1202 can be shared by the first wirelessaccess point. For example, the first wireless access point may havepreviously become aware of the other neighboring access points in itsvicinity based on information in beacons or other management framesreceived from the other access points.

As further described above, after transmitting the CTI frame 1210, thefirst wireless access point may receive, at time t₂, a CTR frame 1212from each of one or more candidate APs that indicates a desire by therespective access point to participate in the TXOP 1202. In the exampleillustrated in FIGS. 12, AP2 and AP3 are among the candidate APs thattransmit respective CTR frames 1212 ₂ and 1212 ₃ to the first wirelessaccess point. Based on the receipt of the CTR frames 1212, the firstwireless access point may then select one or more of the candidate APsto participate in the TXOP 1202.

As described above, in block 1006 of the process 1000 described withreference to FIG. 10, the first wireless access point may allocate arespective set of time and frequency resources of the TXOP 1202 toitself and to each of the selected access points. In someimplementations, the time resources in each set of time and frequencyresources overlap entirely throughout the duration of the TXOP 1202while the frequency resources do not overlap over at least a portion ofthe bandwidth. In some other implementations or instances, the timeresources may also not overlap for at least some portions of theduration. As such, in some implementations, the first wireless accesspoint may further allocate different time resources in addition todifferent frequency resources.

For example, the first wireless access point may divide the availablefrequency resources of the TXOP 1202 into multiple bandwidth segments1220, each comprising one or more frequency resources for itself or oneof the selected access points, and each not overlapping with any of theother bandwidth segments 1220. For example, each of the bandwidthsegments 1220 may include one or more channels (for example, 20 MHzsubchannels) or resource units (RUs) within a bonded wireless channel.In some implementations, the first wireless access point divides theTXOP 1202 into equal bandwidth segments 1220, where the number of equalbandwidth segments 1220 is equal to the number of access points sharingthe TXOP 1202. For example, as illustrated in FIG. 12, the firstwireless access point may partition the TXOP 1202 into two equalbandwidth segments 1220, one bandwidth segment 1220 ₁ for the firstwireless access point and one bandwidth segment 1220 ₂ for the selectedaccess point AP2. In some other implementations or instances, the firstwireless access point may partition the frequency resources into unequalbandwidth segments 1220. For example, the first wireless access pointmay select for itself a wider bandwidth segment 1220 ₁ of the TXOP 1202including more frequency resources than that in the other bandwidthsegments 1220 allocated to the other selected access points. In someimplementations in which the CTR frames 1212 include indications ofbuffer statuses or desired amounts of frequency resources, the firstwireless access point may base the allocations of the frequencyresources to the selected access points based on their respective bufferstatuses or requested frequency resources.

As described above, in block 1008, the first wireless access point mayallocate a subset of time and frequency resources of the TXOP 1202 to atleast a first set of wireless stations in the BSS controlled by thefirst wireless access point for direct wireless communications. Forexample, in some implementations, the first wireless access pointpartitions the available frequency resources of the bandwidth segment1220 ₁ into multiple portions including a portion 1222 ₁ it reserves forregular infrastructure BSS traffic from itself to the first set ofwireless stations or from the first set of wireless stations to itself.The bandwidth segment 1220 ₁ further includes a portion, including thesubset of frequency resources, that may be reserved for direct wirelesscommunications between the first set of wireless stations or otherwireless stations associated with other BSSs. In some implementations,the first set of wireless stations are not permitted to transmit directwireless data communications to other wireless stations outside of thesubset of time and frequency resources reserved for direct wirelesscommunications.

In some implementations, the first wireless access point divides theportion reserved for the direct wireless communications into one ormultiple frequency slots 1224 ₁, each comprising one or more frequencyresources. For example, each of the frequency slots may represent a setof subcarriers (or tones), an RU, or other frequency unit. In someimplementations, each of the frequency slots 1224 ₁ may be separatedfrom each other frequency slot 1224 ₁ by a guard band. In someimplementations, the first wireless access point divides the portionreserved for the direct wireless communications into equal widthfrequency slots 1224 ₁. In some other implementations or instances, thefirst wireless access point may partition the frequency resources intounequal frequency slots 1224. In the illustrated example, the frequencysegment 1220 ₁ includes two frequency slots 1224 _(1A) and 1224 _(2B),although the number of frequency slots 1224 ₁ may be more or less thantwo, and may be adjusted or distributed differently in differentbandwidth segments 1220 within the same TXOP 1202 or subsequent TXOPs1202.

In some such implementations, block 1008 of the process 1000 may furtherinclude allocating each of one or more of the frequency slots 1224 ₁ toa respective subset of the first set of wireless stations (for example,two or more wireless stations) for the direct wireless communications.For example, each subset of wireless stations in the first set ofwireless stations may not be permitted to transmit direct wirelesscommunications in another one of the frequency slots 1224 ₁ allocated toa different subset of wireless stations in the first set of wirelessstations. In some implementations, during at least one of the frequencyslots 1224 ₁, for example, frequency slot 1224 _(1B), at least some (orall) of the first set of wireless stations may be permitted to transmitor receive direct wireless communications to or from other wirelessstations associated with other BSSs controlled by other access pointsincluding AP2 and AP3. In some such implementations, the first wirelessaccess point and other wireless access points may not restrict directwireless communications to any individual BSS in the frequency slot 1224_(1B).

As similarly described above with respect to FIG. 11, the first wirelessaccess point and the selected access points including AP2 may exchangeone or more wireless packets to further coordinate a frequency slotschedule for the frequency slots 1224 in the frequency segments 1220.For example, the exchange may include transmitting, to the selectedaccess points, identifiers of one or more wireless stations in the firstset of wireless stations. The exchange may further include receiving,from the wireless access point AP2, identifiers of one or more wirelessstations associated with the wireless access point that are configuredfor direct wireless communications with other wireless stations. Thefirst wireless access point and the selected wireless access points maycoordinate which wireless stations of the first set of wireless stationsare permitted to transmit direct wireless communications to wirelessstations associated with the other wireless access point during one ormore frequency slots, for example, frequency slots 1224 ₂, allocated tothe selected access point AP2. Similarly, the coordination may includedetermining which wireless stations of the set of wireless stationsassociated with access point AP2 are permitted to transmit directwireless communications to wireless stations in the first set ofwireless stations during one or more time slots of the frequency slots1224 ₁ allocated to the first set of wireless stations.

Similarly, the selected access point AP2 may partition its allocatedfrequency segment 1220 ₂ into a portion 1222 ₂ it reserves for regularinfrastructure BSS traffic with associated wireless stations in its BSS.As described above, the bandwidth segment 1220 ₂ further includes aportion, including a subset of frequency resources, that may be reservedfor direct wireless communications between the respective wirelessstations or other wireless stations associated with other BSSs includingthe first set of wireless stations. As further described above, theselected access point AP2 may divide the portion reserved for the directwireless communications into one or multiple frequency slots 1224 ₂ eachcomprising one or more frequency resources.

As described above, the selected access point AP2 may allocate each ofone or more frequency slots 1224 ₂ to a respective subset of thewireless stations associated with the respective access point for thedirect wireless communications. In some implementations, at least someof the frequency slots 1224 may be coordinated or correspond with eachother. For example, in corresponding common frequency slots 1224 _(1B)and 1224 _(2B) in the bandwidth segment 1220 ₁, at least some (or all)of the wireless stations associated with the respective access pointsmay be permitted to transmit or receive direct wireless communicationsto or from other wireless stations associated with the other BSSscontrolled by the other access point. In some such implementations, thefirst wireless access point and the selected access points may notrestrict direct wireless communications to any individual BSS in thecommon frequency slot.

As described above with reference to FIG. 11, after selecting the accesspoints to participate in the TXOP 1202 in block 1004 and allocating thesets of frequency (and in some implementations, time) resources inblocks 1004 and 1006, the first wireless access point then grants,schedules or otherwise actually allocates (for example, indicates theallocations of) the respective frequency resources to the selectedaccess points in the schedule allocation phase 1206. For example, thefirst wireless access point may transmit, at time t₃, a CTAS frame 1214that includes, for each of the selected access points, the indication ofthe frequency (and in some implementations, time) resources allocated tothe respective access point and usable by the respective access pointand its BSS to transmit data to, or receive data from, one or morerespective associated wireless stations during the TXOP 1202. In suchimplementations, the first wireless packet transmitted by the firstwireless access point in block 1010 of the process 1000 includes theCTAS frame 1214.

As similarly described above, the CTAS frame 1214 may include, for eachof the selected access points, an indication of the frequency resourcesallocated to the respective access point and its BSS. For example, eachtrigger frame of the CTAS frame 1214 may include a user informationfield for each of the selected access points. Each user informationfield includes, for a respective access point, an indication of theallocated frequency resources. For example, the user information fieldmay include an indication of a set of subcarriers, RUs or channelsallocated to the respective access point. In some implementations, theCTAS frame 1214 further includes, for example, in one or more userinformation fields, an indication of a frequency slot schedule, and insome instances, identifiers of the wireless stations allocated use ofthe respective frequency slots. As indicated above, each userinformation field may further include, for the respective selectedaccess point, an indication of time resources available for use by therespective access point while using the respective allocated frequencyresources. In other implementations or instances, the CTAS frame 1214may allocate all of the available time resources to each of the selectedaccess points for use while using their respective allocated frequencyresources.

After transmitting the CTAS frame 1214, the first wireless access point,at time t₄, transmits a CTLS frame 1216 ₁ to the first set of wirelessstations in its BSS. Similarly, the selected access point AP2 may alsotransmit a respective CTLS frame 1216 ₂ to the associated wirelessstations in its respective BSSs at time t₄. Each of the CTLS frames 1216may identify the frequency (and time) resources allocated to therespective access point and its associated BSS, and may indicate thatthe identified frequency resources are reserved for use by, or otherwiseallocated to, the respective BSS.

In some implementations, the second wireless packet transmitted by thefirst wireless access point in block 1012 of the process 1000 includesthe CTLS frame 1216 ₁. In such implementations, the CTLS frame 1216 ₁includes an indication of the subset of time and frequency resourcesallocated to the first set of wireless stations, or other wirelessstations associated with other BSSs, for direct wireless communications.As described above, the indication may include, for each of one or morestations of the first set of wireless stations, an indication of one ormore particular frequency slots 1224 ₁ allocated to the respectivewireless station for direct wireless communications. For example, insome implementations, the CTLS frame 1216 ₁ includes a frequency slotschedule that defines the frequency slots as well as identifiers (forexample, based on BSS color and AID) of the associated wireless stationsallocated use of the respective frequency slots 1224 ₁. In some otherimplementations, the second wireless packet may include the indicationof the subset of time and frequency resources allocated for the directwireless communications in another frame, and may be transmitted, forexample, after transmitting a wireless packet including the CTLS frame1216 ₁. In some implementations, the CTLS frame 1216 ₁ or other framemay include one or more other parameters for the frequency slots 1224 ₁such as, for example, a frame type for direct wireless communicationpermitted to be transmitted in the frequency slots 1224 ₁ or any othercontrol information for controlling direct wireless communication in thefrequency slots.

In some implementations, each of the CTLS frames 1216 transmitted by thefirst wireless access point and the selected access point AP2 includesan IE for each of the access points that includes, for the respectiveaccess point, an indication of the subcarriers, RUs or channels in itsallocated frequency resources. In some implementations, each of the CTLSframes 1216 further includes, for example, in one or more IEs, anindication of the subset of time and frequency resources allocated fordirect wireless communications. For example, an IE may include afrequency slot schedule and identifiers of the wireless stationsallocated use of the respective time slots. As described elsewhereherein, each IE may further include an indication of time resources (forexample, one or more symbols or time slots) available for use whileusing the respective allocated frequency resources.

After the access point and local scheduling during the scheduleallocation phase 1206, the data transmission phase 1208 may begin.During the data transmission phase 1208, the BSSs controlled by thefirst wireless access point and the selected access points AP2 and AP3may share the time and frequency resources of the TXOP 1202 as describedabove. For example, in the first portion 1222 ₁ of the first bandwidthsegment 1220 ₁, the first wireless access point may transmit DLcommunications to, or receive UL communications from, the first set ofwireless stations using any of the SU or MU techniques (for example, MUMIMO or MU OFDMA) described above in the first portion 1222 ₁.

Within the frequency slots 1224 ₁, the first set of wireless stationsmay transmit or receive direct wireless communications to or from otherwireless stations within the BSS controlled by the first wireless accesspoint, and in some implementations or instances, to or from otherwireless stations associated with other BSSs, for example, controlled bythe selected access point AP2 or other selected or non-selected accesspoints. In some implementations, the first wireless access pointrefrains from transmitting in the one or more frequency slots 1224 ₁.

As described above, the first wireless access point may synchronize theselected access points, and in some instances, their respective wirelessstations, in time. For example, in some implementations, in a beginningportion of the data transmission phase 1208, the first wireless accesspoint transmits a CTTRIG frame at time is after the CTLS frames 1216 aretransmitted to synchronize in time the selected access points with thefirst wireless access point. In some implementations, datacommunications may begin a SIFS duration after the CTTRIG frame.

In some implementations, the first set of wireless stations may beenabled for NAN operation and the direct wireless communications mayinclude NAN communications. In some such implementations, the firstwireless access point may permit only the wireless stations in the NANnetwork to access the one or more wireless channels in the time slots1124 or frequency slots 1224 allocated for direct wirelesscommunications. For example, the indication of the subset of time andfrequency resources transmitted in block 1012 may include an indicationof a NAN cluster ID identifying the wireless stations that are allocatedaccess to the one or more wireless channels in the time slots 1124 orfrequency slots 1224. In some implementations, the first set of wirelessstations may not be permitted to transmit direct wireless communicationsto other wireless stations outside of the time slots 1124 or frequencyslots 1224. The first set of wireless stations may operate a NAN networkalone or in combination with other NAN-enabled wireless stations, whichmay be associated with other BSSs controlled by other wireless accesspoints.

In some such implementations, the process 1000 may further includereceiving, from at least one wireless station in the first set ofwireless stations, a wireless packet including an action frame thatindicates one or more parameters associated with the NAN networkincluding a timing of a periodic NAN discovery window. In some otherimplementations, the process 1000 may further include scanning one ormore NAN discovery channels and determining that the first set ofwireless stations is operating a NAN network. The first wireless accesspoint may then identify one or more parameters associated with the NANnetwork including a timing of a NAN discovery window. In some suchimplementations, the first wireless access point may transmit a wirelesspacket to each of one or more other wireless access points that includesan indication of the one or more parameters associated with the NANnetwork. The first wireless access point and the other wireless accesspoints may then synchronize or schedule the time slots 1124 or frequencyslots 1224 based on the one or more parameters associated with the NANnetwork including the timing of the NAN discovery window.

FIG. 13 shows a flowchart illustrating an example process 1300 forwireless communication that supports coordinated D2D communicationsaccording to some implementations. The operations of the process 1300may be implemented by a wireless access point or its components asdescribed herein. For example, the process 1300 may be performed by awireless communication device such as the wireless communication device500 described above with reference to FIG. 5. In some implementations,the process 1300 may be performed by a wireless access point, such asone of the APs 102 and 602 described above with reference to FIGS. 1 and6A, respectively.

In some implementations, in block 1302, the wireless communicationdevice (hereinafter referred to as the first wireless access point withrespect to FIG. 13) receives a first wireless packet from a secondwireless access point that has obtained a TXOP (the TXOP owner). Thefirst wireless packet indicates that multiple time resources andfrequency resources of the TXOP can be shared by the TXOP owner. Inblock 1304, the first wireless access point may transmit a secondwireless packet to the TXOP owner indicating a desire to participate inthe TXOP. In block 1306, the first wireless access point may receive athird wireless packet from the TXOP owner that includes an indication ofa first set of time and frequency resources of the TXOP that have beenallocated to the first wireless access point and its BSS and usable bythe first wireless access point to transmit data to, or receive datafrom, a first set of wireless stations associated with the firstwireless access point during the TXOP. In block 1308, the first wirelessaccess point allocates a first subset of time and frequency resources,of the first set of time and frequency resources allocated to the firstwireless access point, to the first set of wireless stations for directwireless communications with other wireless stations. In block 1310, thefirst wireless access point transmits a fourth wireless packet to thefirst set of wireless stations that includes an indication of the firstsubset of time and frequency resources. Subsequently, the first wirelessaccess point may refrain from transmitting wireless communications inthe first subset of time and frequency resources in block 1312.

As described above with reference to FIGS. 11 and 12, in block 1302, ina TXOP availability indication process in a TXOP indication phase of theTXOP, the first wireless access point may receive the first wirelesspacket from the second wireless access point. The first wireless packetmay advertise an availability of time and frequency resources in theTXOP. For example, the first wireless packet may include a CTI frame asdescribed above. After receiving the CTI frame, the first wirelessaccess point may transmit the second wireless packet in 1304 indicatingthe desire to participate in the TXOP. For example, the second wirelesspacket may include a CTR frame as described above. In block 1306, thefirst wireless access point receives the third wireless packet includingthe indication of the first set of time and frequency resourcesallocated by the second wireless access point to the first wirelessaccess point. For example, the third wireless packet may include a CTASframe as described above.

As described above, in block 1308, the first wireless access point mayallocate a subset of time and frequency resources of the first set oftime and frequency resources to at least a first set of wirelessstations in the BSS controlled by the first wireless access point fordirect wireless communications. For example, in some implementations,the first wireless access point partitions one or both of the availabletime resources and the available frequency resources allocated to itinto multiple portions including a portion it reserves for regularinfrastructure BSS traffic and a portion, including the subset of timeand frequency resources, that is reserved for direct wirelesscommunications between the first set of wireless stations or otherwireless stations associated with other BSSs. As described above withreference to FIGS. 11 and 12, in some implementations, the firstwireless access point divides the portion reserved for the directwireless communications into one or multiple time slots or frequencyslots.

As further described above, after transmitting the CTAS frame, the firstwireless access point may transmit a CTLS frame to the first set ofwireless stations in its BSS. The CTLS frame identifies the time andfrequency resources allocated to the respective access point and itsassociated BSS, and may indicate that the identified time and frequencyresources are reserved for use by, or otherwise allocated to, therespective BSS. In some implementations, the fourth wireless packettransmitted by the first wireless access point in block 1310 includesthe CTLS frame. In such implementations, the CTLS frame includes anindication of the subset of time and frequency resources allocated tothe first set of wireless stations, or other wireless stationsassociated with other BSSs, for direct wireless communications. Asdescribed above, the indication may include, for each of one or morestations of the first set of wireless stations, an indication of one ormore particular time slots or frequency slots allocated to therespective wireless station for direct wireless communications. Thefirst wireless access points, and other wireless access points, mayrefrain from transmitting in the indicated time and frequency slots.

As described above, the first set of wireless stations may be enabledfor NAN operation and the direct wireless communications may include NANcommunications. In some such implementations, the first wireless accesspoint may permit only the wireless stations in the NAN network to accessthe one or more wireless channels in the time slots or frequency slotsallocated for direct wireless communications. In some suchimplementations, the process 1300 may further include receiving awireless packet from the second wireless access point that includes anindication of one or more parameters associated with the NAN network.The first wireless access point and the second wireless access point maythen synchronize or schedule the time slots or frequency slots based onthe one or more parameters associated with the NAN network including thetiming of the NAN discovery window.

FIG. 14 shows a flowchart illustrating an example process 1400 forwireless communication that supports coordinated D2D communicationsaccording to some implementations. The operations of the process 1400may be implemented by a wireless station or its components as describedherein. For example, the process 1400 may be performed by a wirelesscommunication device such as the wireless communication device 500described above with reference to FIG. 5. In some implementations, theprocess 1400 may be performed by a wireless station, such as one of theSTAs 104 and 604 described above with reference to FIGS. 1 and 6B,respectively.

In some implementations, in block 1402, the wireless communicationdevice (hereinafter referred to as the first wireless station withrespect to FIG. 14) receives a first wireless packet from a firstwireless access point that controls a first BSS including a first set ofwireless stations that includes the first wireless station. The firstset of wireless stations are configured for direct wirelesscommunications with other wireless stations. The first wireless packetincludes an indication of a first subset of time and frequency resourcesof a first set of time and frequency resources allocated to the firstBSS. As described above with reference to FIGS. 11 and 12, the first setof time and frequency resources may be one of multiple sets of aplurality of sets of time and frequency resources of a TXOP owned by thefirst wireless access point or by a second wireless access point thatcontrols a second BSS. As further described above, the first wirelessaccess point may allocate the subset of time and frequency resources tothe first set of wireless stations for direct wireless communicationswith other wireless stations. In block 1402, the first wireless stationstransmits a second wireless packet directly to another wireless stationusing one or more of the time and frequency resources in the firstsubset of time and frequency resources allocated to the first wirelessstation. For example, the second wireless packet may be a SU PPDU thatmay be transmitted according to the 802.11be or later amendments to theIEEE 802.11 specification.

As described above with reference to FIGS. 11 and 12, in someimplementations, the first wireless access point partitions one or bothof the first set of available time resources and available frequencyresources allocated to the first BSS into multiple portions including aportion it reserves for regular infrastructure BSS traffic and aportion, including the subset of time and frequency resources, that isreserved for direct wireless communications between the first set ofwireless stations or other wireless stations associated with other BSSs.As further described above, in some implementations, the first wirelessaccess point divides the portion reserved for the direct wirelesscommunications into one or multiple time slots or frequency slots.

In some implementations, the first wireless packet may be the wirelesspacket carrying the CTLS frame to the first set of wireless stations. Asdescribed above, the CTLS frame may include a first identification ofthe first set of time and frequency resources allocated to therespective BSS and a second indication of the subset of time andfrequency resources allocated to the first set of wireless stations, orother wireless stations associated with other BSSs, for direct wirelesscommunications. As described above, the indication may include, for thefirst wireless station, an indication of one or more particular timeslots or frequency slots allocated to the first wireless station andother wireless stations inside or outside of the first BSS for directwireless communications. The first wireless station may then contend foraccess to the wireless medium during the respective slots.

As described above, the first set of wireless stations may be enabledfor NAN operation and the direct wireless communications may include NANcommunications. In some such implementations, the first wireless accesspoint may permit only the wireless stations in the NAN network to accessthe one or more wireless channels in the time slots or frequency slotsallocated for direct wireless communications. The first wireless stationmay form or join a NAN network prior to or after association with thefirst wireless access point. In some implementations, the first wirelessstation is configured to transmit a wireless packet including an actionframe to the first wireless access point that indicates one or moreparameters associated with the NAN network including a timing of a NANdiscovery window. In some other implementations, the first wirelessstation may periodically broadcast wireless packets that indicate one ormore parameters associated with the NAN network including a timing of aNAN discovery window. In some implementations, the first set of wirelessstations are not permitted to transmit direct wireless communications toother wireless stations outside of the first subset of time andfrequency resources allocated to the first set of wireless stationsexcept for direct wireless communications in NAN discovery windows. Inother words, the first set of wireless stations are not permitted totransmit direct wireless data communications outside of the allocatedtime and frequency slots.

In some implementations, in one or more of the allocated time andfrequency slots, the first wireless station may exchange one or morewireless packets with at least one other wireless station in the NANnetwork to set up a NAN data link (NDL) in the allocated time andfrequency slots. In such implementations, the first wireless station maytransmit the second wireless packet directly to the other wirelessstation via the NDL.

Some wireless communication protocols, including those supporting IEEE802.11 standards, support the use of quiet periods. Each quiet periodrefers to a duration of time during which no wireless communicationdevices, including APs and STAs, are generally permitted to access anindicated wireless channel or channels of the shared frequency band. Oneinitial motivation for the support of quiet periods was to permit an APto perform measurements without interference, for example, measurementsfor dynamic frequency selection (DFS) purposes. In some implementations,quiet periods may be recurring, for example, based on a given beaconinterval. Additionally, more than one quiet period may be defined foreach beacon interval.

Various other aspects relate generally to synchronized channel accesstechniques. Each synchronized coordinated access window may include ascheduled contention period, during which multiple synchronized accesspoints contend for access, followed by a communication period duringwhich the successful AP holds a TXOP. In some implementations,synchronized access points may schedule periodically recurring,synchronized coordinated access windows by periodically transmittingquiet elements. The quiet elements establish recurring quiet periodsduring which legacy devices are not permitted to transmit. The wirelessaccess points may also transmit one or more quiet override elementsassociated with respective quiet elements. A quiet override elementindicates to the synchronized access points, and in some instance, theirassociated wireless stations, that the quiet period established by therespective quiet element is to be used for synchronized channel access,and as such, that the synchronized APs are permitted to contend foraccess during the respective contention period1604. In someimplementations, the wireless access points may schedule reserved accesswindows within the coordinated access windows during which D2D-enabledwireless devices are permitted to transmit direct wirelesscommunications to other D2D-enabled wireless devices.

FIG. 15 shows a flowchart illustrating an example process 1500 forwireless communication that supports coordinated D2D communicationsaccording to some implementations. The operations of the process 1500may be implemented by a wireless access point or its components asdescribed herein. For example, the process 1500 may be performed by awireless communication device such as the wireless communication device500 described above with reference to FIG. 5. In some implementations,the process 1500 may be performed by a wireless access point, such asone of the APs 102 and 602 described above with reference to FIGS. 1 and6A, respectively.

In block 1502, the wireless communication device (hereinafter referredto as the first wireless access point with respect to FIG. 15) exchangesone or more first wireless packets with a first set of wireless accesspoints that includes the first wireless access point to coordinate aschedule of periodic coordinated access windows during which the firstset of wireless access points are scheduled to contend for access to oneor more wireless channels. In block 1504, the first wireless accesspoint transmits a second wireless packet that includes a firstindication of the periodic coordinated access windows. In block 1506,the first wireless access point determines that a first set of wirelessstations in a first BSS controlled by the first wireless access point isoperating a NAN network, each wireless station in the first set ofwireless stations being configured for direct wireless communicationswith other wireless stations in the NAN network. In someimplementations, the first set of wireless stations not being permittedto contend for access to the one or more wireless channels during theperiodic coordinated access windows. In block 1508, the first wirelessaccess point transmits a third wireless packet to the first set ofwireless stations that includes a second indication of a reserved accesswindow within one or more of the periodic coordinated access windows.The second indication indicates that the first set of wireless stationsare permitted to transmit direct wireless communications to otherwireless stations in the NAN network on the one or more wirelesschannels despite the first indication. The first wireless access pointmay then refrain from transmitting wireless communications during thereserved access windows in block 1510.

FIG. 16 shows a timing diagram illustrating example reserved accesswindows that support coordinated D2D communications according to someimplementations. For example, FIG. 16 shows synchronized, recurringcoordinated access windows 1602 (for example, including a firstcoordinated access window 1602 ₁, a second coordinated access window1602 ₂ and a third coordinated access window 1602 ₃). The coordinatedaccess windows 1602 recur according to a periodicity indicated by a timeinterval τ_(Access). Each coordinated access window 1602 includes arespective contention period 1604 (for example, contention periods 1604₁, 1604 ₂ and 1604 ₃) at the start of the coordinated access windowhaving a duration τ_(Cntd). Each coordinated access window 1602 alsoincludes a respective communication period 1606 (for example,communication periods 1606 ₁, 1606 ₂ and 1606 ₃) having a durationτ_(Comm). In some implementations, only during the contention periods1604, at the start of the scheduled coordinated access windows 1602, dothe first set of wireless access points enabled for synchronized channelaccess, and desiring to communicate over the wireless medium, contendfor access. The first set of wireless stations are not permitted tocontend for access to the one or more wireless channels during anyportion of the periodic coordinated access windows 1602. In someimplementations, between adjacent coordinated access windows 1602, theremay be open periods having duration τ_(Open) during which the wirelessmedium is open for regular contention-based access by other wirelesscommunication devices (and optionally also by the synchronized APs) asgoverned by, for example, the CSMA/CA and EDCA techniques.

The second wireless packet transmitted in block 1504 includes channelaccess information establishing one or more recurring synchronizedcoordinated access windows 1602. In some implementations, the channelaccess information is conveyed by one or more quiet elements and one ormore quiet override elements included within the first wireless packets.Each quiet element indicates to a second set of wireless communicationdevices (that may include the first set of wireless access points andthe first set of wireless stations) that they are not permitted totransmit on a wireless channel during a quiet period defined by thequiet element. In some implementations, a quiet override elementindicates to the first set of wireless access points, for each of one ormore of the quiet elements, whether they are permitted to contend foraccess to the wireless channel during a contention period of the quietperiod defined by the respective quiet element. In this way, the firstset of wireless access points may schedule periodically recurring,synchronized coordinated access windows, such as synchronizedcoordinated access windows 1602 described with reference to FIG. 16, byestablishing periodic quiet periods.

If a quiet override element indicates that the first set of wirelessaccess points is permitted to contend for access during respectivecontention periods 1604 of each of one or more upcoming quiet periods,then each of the first set of wireless access points may contend foraccess to the wireless channel during one or more of the contentionperiods 1604 indicated by the respective quiet elements and the quietoverride element. If the first wireless access point wins the contentionduring one of the contention periods 1604, it is then the owner of aTXOP on the wireless channel during the respective communication period1606 of the respective coordinated access window 1602. The firstwireless access point may then exchange one or more wireless datapackets on the wireless channel during the TXOP.

As described above, the quiet elements establish recurring quiet periodsduring which compatible devices receiving the quiet elements aregenerally not permitted to transmit. In such a manner, synchronizedchannel access may be protected. For example, the compatible devices mayinclude the first set of wireless access points and the first set ofwireless stations. The first set of wireless access points are accesspoints that support synchronized channel access (synchronized accesspoints). However, while no devices are generally permitted to contendfor access during quiet periods, a quiet override element indicates tothe first set of wireless access points (and to the first set ofwireless stations) that a quiet period established by a respective quietelement is to be used for synchronized channel access, and as such, thatthe first set of wireless access points is permitted to contend foraccess during the respective contention period 1604. Additionally, thefirst set of wireless stations that support synchronized channel accessmay also understand the quiet override element, and as such, may beconfigured to receive DL communications from the first wireless accesspoint during a quiet period and, in response to receiving a triggerframe from the first wireless access point, transmit UL communicationsto the first wireless access point during the quiet period.

The second set of wireless communication devices may also include legacydevices, which may be devices configured to operate according to theIEEE 802.11ax or earlier amendments or versions of the IEEE 802.11family of standards but not configured to operate according to the IEEE802.11be or later amendments or versions of the IEEE 802.11 family ofstandards. The second set of wireless communication devices may alsoinclude devices that do not otherwise support, or which have disabled ornot implemented, synchronized channel access. The second set of wirelesscommunication devices may be configured to interpret the quiet elementsbut may not be configured to interpret the quiet override elements.

For example, exchanging the one or more first wireless packets includingthe channel access information in block 1502 may include broadcasting,multicasting, otherwise transmitting, or receiving frames, such asmanagement frames, that include or indicate the quiet elements and quietoverride element. For example, the channel access information includingthe quiet elements and quiet override element may be shared in beacons1608 (including beacons 1608 ₁, 1608 ₂ and 1608 ₃) or in probe responseframes. For example, the beacon 1608 ₁ may include a first quiet elementand quiet override element that identifies a first quiet period to beused by the first set of wireless access points as the coordinatedaccess window 1602 ₁.

In some implementations or instances in which the first wireless accesspoint may or may not be (or configured to operate within) a master (orcontrolling) access point, the first wireless access point may transmita first wireless packet including the channel access information to theother synchronized access points in the first set of wireless accesspoints in block 1502. Alternatively, in some other implementations orinstances, again, in which the first wireless access point may or maynot be (or configured to operate within) a master (or controlling)access point, the first wireless access point may receive a firstwireless packet including the channel access information from at leastone other synchronized access point in the first set of wireless accesspoints in block 1502.

The channel access information exchanged in block 1502 may includevarious channel access parameters associated with the recurringcoordinated access windows 1602 such as, for example, one or more of therelevant wireless channel or channels for which the scheduled channelaccess is defined, a start time of the next coordinated access window1602, the time interval τ_(Access) between the starts of consecutivecoordinated access windows 1602, the duration τ_(Cntd) of eachcontention period 1604, the duration τ_(Comm) of each communicationperiod 1606, or the total duration of each coordinated access window1602. As described above, each of the quiet periods, and thus thecoordinated access windows 1602, may recur according to a TBTT or othertime interval.

As described above, while devices are generally not permitted to contendfor access during quiet periods, a quiet override element indicates tothe first set of wireless access points (and in some instances the firstset of wireless stations) that a quiet period established by arespective quiet element is to be used for synchronized channel access,and as such, that the first set of wireless access points is permittedto contend for access during a respective contention period 1604 of arespective synchronized coordinated access window 1602. The quietoverride element may include multiple fields including an element ID, alength, and a quiet override map, as well as, in some implementations, aduration field or a reserved field. The quiet override map may include abitmap in which each bit is associated with a respective quiet element.A value of each bit in the bitmap may indicate whether the quiet perioddefined by a respective quiet element is to be used as a synchronizedcoordinated access window 1602, and as such, whether the first set ofwireless access points is permitted to contend for access during acontention period 1604 of the respective coordinated access window 1602defined by the quiet element associated with the bit. The duration fieldmay indicate a duration of each contention period 1604. For example, theduration field may include a 4-bit value indicating a duration to beused for all contention periods (in some other implementations, theduration field may include multiple sub-fields each indicating aduration of a respective contention period for a respective quietperiod). In some other examples, another field in a beacon or othermanagement frame shared by the synchronized access points may be used tosignal the durations of the contention periods.

As described above, if the first wireless access point wins thecontention during one of the contention periods 1604, it is then theowner of a TXOP on the wireless channel during the respectivecommunication period 1606 of the respective coordinated access window1602. The first wireless access point may then exchange one or morewireless data packets to the first set of wireless stations on thewireless channel during the TXOP. For example, the first wireless accesspoint may transmit DL data to one or more of the first set of wirelessstations. Additionally or alternatively, the first wireless access pointmay receive UL data from one or more of the first set of wirelessstations.

In some implementations, the first set of wireless access points maysignal their support for synchronized channel access to other ones ofthe first wet of wireless access points (as well as to associatedwireless stations) in management frames, such as beacon frames and proberesponse frames, or other frames transmitted between the synchronizedaccess points. For example, the first set of wireless access points maysignal their support for synchronized channel access in an operationelement included within the beacon, probe response or other frames. Thefirst set of wireless access points may also receive management frames,such as probe requests, from associated wireless stations including thefirst set of wireless stations indicating that the stations supportsynchronized channel access. For example, the wireless stations maysignal their support for synchronized channel access in a capabilityelement included within probe request frames.

In some implementations, the first set of wireless access points mayreceive one or more explicit synchronization signals from either adedicated controller or another access point operating as a master (orcontrolling) access point. The first set of wireless access points maysynchronize their respective clocks based on the synchronization signalsto facilitate the implementation of the recurring coordinated accesswindows. In some other implementations, the first set of wireless accesspoints may synchronize their clocks based on the receipt of variousframes (for example, beacons or other management frames, control framesor data frames) from other ones of the first set of wireless accesspoints participating in the recurring coordinated access windows.

As described above, each wireless station in the first set of wirelessstations is also configured for D2D communications (also referred togenerally herein as direct wireless communications) with other wirelessstations. In particular implementations, the first set of wirelessstations operate a NAN network alone or in combination with otherNAN-enabled wireless stations associated with other wireless accesspoints. As further described above, in block 1506, the first wirelessaccess point determines that the first set of wireless stations isoperating the NAN network. For example, in some implementations thedetermination in block 1506 includes scanning one or more NAN discoverychannels to determine whether the first set of wireless stations isoperating a NAN network. Additionally or alternatively, thedetermination in block 1506 may be based on receiving a wireless packetincluding an action frame from one or more of the first set of wirelessstations that indicates one or more parameters associated with the NANnetwork including a timing of a NAN discovery window.

In some implementations, responsive to determining that the first set ofwireless stations is operating the NAN network, the first wirelessaccess point transmits the third wireless packet in block 1508 to thefirst set of wireless stations that includes the second indication of areserved access window 1610 that is within one or more of the periodiccoordinated access windows 1602, for example, during a portion of therespective communication period 1606 (such as an ending portion of thecommunication period 1606 as shown). In some implementations, the secondpacket and the third wireless packet may be the same packet; that is, asingle wireless packet may include both the first indication of thecoordinated access windows 1602 and the second indication of thereserved access windows 1610. The second indication indicates that thefirst set of wireless stations are permitted to transmit direct wirelesscommunications to other wireless stations in the NAN network on the oneor more wireless channels despite the first indication. The first set ofwireless stations may then contend for access to the wireless mediumduring one or more portions of the reserved access windows 1610. Thefirst wireless access point may refrain from transmitting wirelesscommunications during the reserved access windows 1610.

In some implementations, the first set of wireless stations are notpermitted to transmit direct wireless data communications to otherwireless stations outside of reserved access windows 1610 (but they maybe able to transmit other direct non-data wireless communications in,for example, discovery windows outside of the coordinated access windows1602). In some implementations, the indication of the periodic reservedaccess windows 1610 indicates to the first set of wireless stations thatthey are permitted to transmit direct wireless communications to otherwireless stations outside of the first set of wireless stations (forexample, in other BSSs managed by other wireless access points) duringat least a portion of one or more of the reserved access windows 1610.In some implementations, the indication of the reserved access windows1610 indicates to other wireless stations in other BSSs that they arepermitted to transmit direct wireless communications to other wirelessstations, which may include the first set of wireless stations, on theone or more wireless channels during at least a portion of one or moreof the reserved access windows 1610.

In some implementations, the process 1600 further includes exchangingone or more wireless packets with one or more other access points in thefirst set of wireless access points to coordinate a schedule of periodicreserved access windows 1610. For example, the exchange of the one ormore wireless packets may include transmitting beacons and receivingbeacons from the other wireless access points that each include timinginformation for coordinating the schedule of the periodic reservedaccess windows 1610.

In some implementations, the indication of the reserved access windows1610 includes one or more other parameters for the reserved accesswindows 1610. In some implementations, the one or more other parametersinclude a time slot schedule defining a series of time slots in thereserved access windows 1610. In some implementations, each of the timeslots may be separated from each other time slot by an IFS (for example,a SIFS). The number of time slots may vary, and may be adjusted ordistributed differently in different reserved access windows 1610 indifferent coordinated access windows 1602. In some such implementations,the process 1500 further includes allocating each of one or more of thetime slots to a respective subset of the first set of wireless stations(for example, two or more wireless stations) for the direct wirelesscommunications. For example, each subset of wireless stations in thefirst set of wireless stations may not be permitted to transmit directwireless communications in another time slot allocated to a differentsubset of wireless stations in the first set of wireless stations.

In some implementations, during at least one of the time slots, at leastsome of the first set of wireless stations may be permitted to transmitor receive direct wireless communications to or from other wirelessstations in the NAN network associated with other BSSs controlled byother access points. In some such implementations, the first wirelessaccess point and other wireless access points may not restrict directwireless communications to any individual BSS in at least one of thetime slots. Additionally or alternatively, the first wireless accesspoint and the other wireless access points may exchange one or morewireless packets to further coordinate a time slot schedule for the timeslots within at least one of the reserved access windows. In some suchimplementations, the exchange includes transmitting, to at least one ofthe wireless access points, identifiers of one or more wireless stationsin the first set of wireless stations. The exchange further includesreceiving, from the wireless access point, identifiers of one or morewireless stations associated with the wireless access point that areconfigured for direct wireless communications with other wirelessstations. The two wireless access points may coordinate which wirelessstations of the first set of wireless stations are permitted to transmitdirect wireless communications to wireless stations associated with theother wireless access point during one or more time slots allocated tothe other wireless access point. Similarly, the coordination may includedetermining which wireless stations of the set of wireless stationsassociated with the other wireless access point are permitted totransmit direct wireless communications to wireless stations in thefirst set of wireless stations during one or more time slots allocatedto the first set of wireless stations.

In some implementations, the one or more other parameters identified inthe indication of the reserved access window 1610 may further include aframe type for direct wireless communication permitted to be transmittedduring the reserved access window 1610 or any other control informationfor controlling direct wireless communication during the reserved accesswindow 1610.

In some implementations, the process 1500 further includes transmittinga trigger frame to the first set of wireless stations at a beginning ofa reserved access window 1610 that triggers or initiates direct wirelesscommunications by the wireless stations in the first set of wirelessstations. For example, the trigger frame may indicate to the first setof wireless stations that they are permitted to contend for accessduring the respective slots within the reserved access window 1610. Insome other implementations, the process 1500 may further includetransmitting an RDG frame to one or more of the wireless stations in thefirst set of wireless stations to initiate the direct wirelesscommunications with other wireless stations.

FIG. 17 shows a flowchart illustrating an example process 1700 forwireless communication that supports coordinated D2D communicationsaccording to some implementations. The operations of the process 1700may be implemented by a wireless station or its components as describedherein. For example, the process 1700 may be performed by a wirelesscommunication device such as the wireless communication device 500described above with reference to FIG. 5. In some implementations, theprocess 1700 may be performed by a wireless station, such as one of theSTAs 104 and 604 described above with reference to FIGS. 1 and 6B,respectively.

In block 1702, the wireless communication device (hereinafter referredto as the first wireless station with respect to FIG. 17) forms or joinsa NAN network including a first set of wireless stations that includesthe first wireless station. Each wireless station in the first set ofwireless stations is configured for direct wireless communications withother wireless stations in the NAN network. In block 1704, the firstwireless station receives a first wireless packet from a first wirelessaccess point that controls a first BSS that includes the first set ofwireless stations. The first wireless packet includes a first indicationof periodic coordinated access windows during which wireless accesspoints, including the first wireless access point, are scheduled tocontend for access to one or more wireless channels, and during whichwireless stations, including the first set of wireless stations, are notpermitted to contend for access to the one or more wireless channels. Inblock 1706, the first wireless station receives a second wireless packetfrom the first wireless access point that includes a second indicationof a reserved access window within one or more of the periodiccoordinated access windows, the second indication indicating that thefirst set of wireless stations are permitted to transmit direct wirelesscommunications to other wireless stations in the NAN network on the oneor more wireless channels despite the first indication. In block 1708,the first wireless station transmits a third wireless packet directly toanother wireless station during at least one of the reserved accesswindows.

The first wireless packet received in block 1704 includes channel accessinformation establishing one or more recurring synchronized coordinatedaccess windows 1602 as described above with respect to FIG. 16. Thefirst set of wireless stations are not permitted to contend for accessto the one or more wireless channels during any portion of the periodiccoordinated access windows 1602. As described above, in someimplementations, the channel access information is conveyed by one ormore quiet elements and one or more quiet override elements includedwithin the first wireless packets. Each quiet element indicates to a setof wireless communication devices, that may include a first set ofwireless access points and the first set of wireless stations, that theyare not permitted to transmit on a wireless channel during a quietperiod defined by the quiet element. In some implementations, a quietoverride element indicates to the first set of wireless access points,for each of one or more of the quiet elements, whether they arepermitted to contend for access to the wireless channel during acontention period of the quiet period defined by the respective quietelement. In this way, the first set of wireless access points mayschedule periodically recurring, synchronized coordinated accesswindows, such as synchronized coordinated access windows 1602 describedwith reference to FIG. 16, by establishing periodic quiet periods.

As described above, the quiet elements establish recurring quiet periodsduring which compatible devices receiving the quiet elements aregenerally not permitted to transmit. In such a manner, synchronizedchannel access may be protected. For example, the compatible devices mayinclude the first set of wireless access points and the first set ofwireless stations. The first set of wireless access points are accesspoints that support synchronized channel access (synchronized accesspoints). However, while no devices are generally permitted to contendfor access during quiet periods, a quiet override element indicates tothe first set of wireless access points (and to the first set ofwireless stations) that a quiet period established by a respective quietelement is to be used for synchronized channel access, and as such, thatthe first set of wireless access points is permitted to contend foraccess during the respective contention period 1604. Additionally, thefirst set of wireless stations that support synchronized channel accessmay also understand the quiet override element, and as such, may beconfigured to receive DL communications from the first wireless accesspoint during a quiet period and, in response to receiving a triggerframe from the first wireless access point, transmit UL communicationsto the first wireless access point during the quiet period.

As described above, each wireless station in the first set of wirelessstations is also configured for D2D communications with other wirelessstations. In particular implementations, the first set of wirelessstations operate a NAN network alone or in combination with otherNAN-enabled wireless stations associated with other wireless accesspoints. In some implementations, the first wireless station transmits awireless packet to the first wireless access point that includes one ormore parameters for the NAN network including a timing of a NANdiscovery window. In some other implementations, the first wirelessstation may schedule the NAN discovery window for the NAN network toperiodically begin at a fixed duration of time after each periodiccoordinated access window 1602. In some implementations, the firstwireless station may also transmit, in the NAN discovery windows, anindication of the periodic coordinated access windows 1602 to otherwireless stations in the NAN network.

As described above, in block 1706, the first wireless station receivesthe second wireless packet from the first wireless access point thatincludes the second indication of the reserved access window 1610 withinone or more of the periodic coordinated access windows 1602. As furtherdescribed above, the second indication indicating that the first set ofwireless stations are permitted to transmit direct wirelesscommunications to other wireless stations in the NAN network on the oneor more wireless channels despite the first indication. In someimplementations, the second packet and the third wireless packet may bethe same packet; that is, a single wireless packet may include both thefirst indication of the coordinated access windows 1602 and the secondindication of the reserved access windows 1610.

In some implementations, the first set of wireless stations are notpermitted to transmit direct wireless data communications to otherwireless stations outside of reserved access windows 1610 (but they maybe able to transmit other direct non-data wireless communications in,for example, discovery windows outside of the coordinated access windows1602). In some implementations, the second indication of the reservedaccess windows 1610 received in block 1706 indicates to the first set ofwireless stations that they are permitted to transmit direct wirelesscommunications to other wireless stations outside of the first set ofwireless stations (for example, in other BSSs managed by other wirelessaccess points) during at least a portion of one or more of the reservedaccess windows 1610. In some implementations, the indication of thereserved access windows 1610 received in block 1706 indicates to otherwireless stations in other BSSs that they are permitted to transmitdirect wireless communications to other wireless stations, which mayinclude the first set of wireless stations, on the one or more wirelesschannels during at least a portion of one or more of the reserved accesswindows 1610.

In some implementations, the indication of the reserved access windows1610 received in block 1706 includes one or more other parameters forthe reserved access windows 1610. In some implementations, the one ormore other parameters include a time slot schedule defining a series oftime slots in the reserved access windows 1610. In some implementations,each of the time slots may be separated from each other time slot by anIFS (for example, a SIFS). The number of time slots may vary, and may beadjusted or distributed differently in different reserved access windows1610 in different coordinated access windows 1602. In some suchimplementations, each of one or more of the time slots may be allocatedto a respective subset of the first set of wireless stations (forexample, two or more wireless stations) for the direct wirelesscommunications. For example, each subset of wireless stations in thefirst set of wireless stations may not be permitted to transmit directwireless communications in another time slot allocated to a differentsubset of wireless stations in the first set of wireless stations. Insome implementations, during at least one of the time slots, at leastsome of the first set of wireless stations may be permitted to transmitor receive direct wireless communications to or from other wirelessstations in the NAN network associated with other BSSs controlled byother access points. In some such implementations, the first wirelessaccess point and other wireless access points may not restrict directwireless communications to any individual BSS in at least one of thetime slots.

In some implementations, the one or more other parameters identified inthe indication of the reserved access window 1610 may further include aframe type for direct wireless communication permitted to be transmittedduring the reserved access window 1610 or any other control informationfor controlling direct wireless communication during the reserved accesswindow 1610.

In some implementations, the process 1700 further includes receiving atrigger frame from the first wireless access point at a beginning of areserved access window 1610 that triggers or initiates direct wirelesscommunications by the first wireless station. For example, the firstwireless station may contend for access during the respective slotswithin the reserved access window 1610 based on the receipt of thetrigger frame. In some other implementations, the process 1700 mayfurther include receiving an RDG frame from the first wireless accesspoint to initiate the direct wireless communications with other wirelessstations.

FIG. 18 shows a block diagram of an example wireless communicationdevice 1800 that supports coordinated D2D communications according tosome implementations. In some implementations, the wirelesscommunication device 1800 is configured to perform the process 1100described above with reference to FIG. 11. The wireless communicationdevice 1800 may be an example implementation of the wirelesscommunication device 500 described above with reference to FIG. 5. Forexample, the wireless communication device 1800 can be a chip, SoC,chipset, package or device that includes at least one modem (forexample, a Wi-Fi (IEEE 802.11) modem or a cellular modem such as themodem 502), at least one processor (such as the processor 504) and atleast one memory (such as the memory 508). The wireless communicationdevice 1800 may further include at least one radio (such as the radio506). In some implementations, the wireless communication device 1800can be a device for use in an AP, such as one of the APs 102 and 602described above with reference to FIGS. 1 and 6A, respectively. In someother implementations, the wireless communication device 1800 can be anAP that includes such a chip, SoC, chipset, package or device as well asat least one antenna (such as the antennas 620).

The wireless communication device 1800 includes a reception component1810, a communication manager 1820, and a transmission component 1830.The communication manager 1820 further includes a coordinated accesscomponent 1822. Portions of the coordinated access component 1822 may beimplemented at least in part in hardware or firmware. In someimplementations, the coordinated access component 1822 is implemented atleast in part as software stored in the memory. For example, portions ofthe coordinated access component 1822 can be implemented asnon-transitory instructions (or “code”) executable by the processor toperform the functions or operations of the respective component.

The reception component 1810 is configured to receive RX signalsrepresenting uplink communications from wireless stations orcommunications from other APs. The transmission component 1830 isconfigured to transmit TX signals representing downlink communicationsto the wireless stations or communications to other APs. In someimplementations, the coordinated access component 1822 is configured togenerate and cause the transmission component 1830 to transmit a firstwireless packet to at least a first set of wireless stations in a firstBSS controlled by the first wireless access point, each wireless stationin the first set of wireless stations being configured for directwireless communications with other wireless stations. The first wirelesspacket may include an indication of periodic reserved access windowsindicating to the first set of wireless stations that they are permittedto transmit direct wireless communications to other wireless stations inthe first set of wireless stations on one or more wireless channelsduring the periodic reserved access windows. The coordinated accesscomponent 1822 is further configured to refrain from causing thetransmission component 1830 to transmit wireless communications duringthe periodic reserved access windows.

FIG. 19 shows a block diagram of an example wireless communicationdevice 1900 that supports coordinated D2D communications according tosome implementations. In some implementations, the wirelesscommunication device 1900 is configured to perform the process 1200described above with reference to FIG. 12. The wireless communicationdevice 1900 may be an example implementation of the wirelesscommunication device 500 described above with reference to FIG. 5. Forexample, the wireless communication device 1900 can be a chip, SoC,chipset, package or device that includes at least one modem (forexample, a Wi-Fi (IEEE 802.11) modem or a cellular modem such as themodem 502), at least one processor (such as the processor 504) and atleast one memory (such as the memory 508). The wireless communicationdevice 1900 may further include at least one radio (such as the radio506). In some implementations, the wireless communication device 1900can be a device for use in a STA, such as one of the STAs 104 and 604described above with reference to FIGS. 1 and 6A, respectively. In someother implementations, the wireless communication device 1900 can be aSTA that includes such a chip, SoC, chipset, package or device as wellas at least one antenna (such as the antennas 625).

The wireless communication device 1900 includes a reception component1910, a communication manager 1920, and a transmission component 1930.The communication manager 1920 further includes a coordinated accesscomponent 1922. Portions of the coordinated access component 1922 may beimplemented at least in part in hardware or firmware. In someimplementations, the coordinated access component 1922 is implemented atleast in part as software stored in the memory. For example, portions ofthe coordinated access component 1922 can be implemented asnon-transitory instructions (or “code”) executable by the processor toperform the functions or operations of the respective component.

The reception component 1910 is configured to receive RX signalsrepresenting downlink communications from a wireless access point orcommunications directly from other wireless stations. The transmissioncomponent 1930 is configured to transmit TX signals representing uplinkcommunications to the wireless access point or communications directlyto other wireless stations. In some implementations, the coordinatedaccess component 1922 is configured to receive, via the receptioncomponent 1910, a first wireless packet from a first wireless accesspoint that controls a first BSS including a first set of wirelessstations that includes the first wireless station, the first wirelessstation being configured for direct wireless communications with otherwireless stations. The first wireless packet may include an indicationof periodic reserved access windows indicating to the first wirelessstation that it is permitted to transmit direct wireless communicationsto one or more other wireless stations in the first set of wirelessstations on one or more wireless channels during the periodic reservedaccess windows. The coordinated access component is further configuredto generated and cause the transmission component 1930 to transmit asecond wireless packet directly to another wireless station during atleast one of the periodic reserved access windows.

FIG. 20 shows a block diagram of an example wireless communicationdevice 2000 that supports coordinated D2D communications according tosome implementations. In some implementations, the wirelesscommunication device 2000 is configured to perform the process 1300described above with reference to FIG. 13. The wireless communicationdevice 2000 may be an example implementation of the wirelesscommunication device 500 described above with reference to FIG. 5. Forexample, the wireless communication device 2000 can be a chip, SoC,chipset, package or device that includes at least one modem (forexample, a Wi-Fi (IEEE 802.11) modem or a cellular modem such as themodem 502), at least one processor (such as the processor 504) and atleast one memory (such as the memory 508). The wireless communicationdevice 2000 may further include at least one radio (such as the radio506). In some implementations, the wireless communication device 2000can be a device for use in an AP, such as one of the APs 102 and 602described above with reference to FIGS. 1 and 6A, respectively. In someother implementations, the wireless communication device 2000 can be anAP that includes such a chip, SoC, chipset, package or device as well asat least one antenna (such as the antennas 620).

The wireless communication device 2000 includes a reception component2010, a communication manager 2020, and a transmission component 2030.The communication manager 2020 further includes a coordinated accesscomponent 2022. Portions of the coordinated access component 2022 may beimplemented at least in part in hardware or firmware. In someimplementations, the coordinated access component 2022 is implemented atleast in part as software stored in the memory. For example, portions ofthe coordinated access component 2022 can be implemented asnon-transitory instructions (or “code”) executable by the processor toperform the functions or operations of the respective component.

The reception component 2010 is configured to receive RX signalsrepresenting uplink communications from wireless stations orcommunications from other APs. The transmission component 2030 isconfigured to transmit TX signals representing downlink communicationsto the wireless stations or communications to other APs. In someimplementations, the coordinated access component 2022 is configured tocontend for access to the medium to obtain a transmission opportunityfor wireless communication via one or more wireless channels. Thecoordinated access component 2022 also is configured to select one ormore other wireless access points to participate in the transmissionopportunity. The coordinated access component 2022 also is configured toallocate a respective set of time and frequency resources of a pluralityof sets of time and frequency resources of the transmission opportunityto each of the first wireless access point and the selected wirelessaccess points. The coordinated access component 2022 also is configuredto allocate a first subset of time and frequency resources, of the setof time and frequency resources allocated to the first wireless accesspoint, to a first set of wireless stations in a BSS controlled by thefirst wireless access point for direct wireless communications withother wireless stations. The coordinated access component 2022 also isconfigured to generate and cause the transmission component 2030 totransmit a first wireless packet to the one or more selected wirelessaccess points that includes, for each of the selected wireless accesspoints, an indication of the set of time and frequency resourcesallocated to the respective wireless access point. The coordinatedaccess component 2022 is additionally configured to generate and causethe transmission component 2030 to transmit a second wireless packet tothe first set of wireless stations that includes an indication of thefirst subset of time and frequency resources. The coordinated accesscomponent 2022 is further configured to refrain from causing thetransmission component 1030 to transmit wireless communications in thefirst subset of time and frequency resources.

FIG. 21 shows a block diagram of an example wireless communicationdevice 2100 that supports coordinated D2D communications according tosome implementations. In some implementations, the wirelesscommunication device 2100 is configured to perform the process 1400described above with reference to FIG. 14. The wireless communicationdevice 2100 may be an example implementation of the wirelesscommunication device 500 described above with reference to FIG. 5. Forexample, the wireless communication device 2100 can be a chip, SoC,chipset, package or device that includes at least one modem (forexample, a Wi-Fi (IEEE 802.11) modem or a cellular modem such as themodem 502), at least one processor (such as the processor 504) and atleast one memory (such as the memory 508). The wireless communicationdevice 2100 may further include at least one radio (such as the radio506). In some implementations, the wireless communication device 2100can be a device for use in a AP, such as one of the APs 102 and 602described above with reference to FIGS. 1 and 6A, respectively. In someother implementations, the wireless communication device 2100 can be anAP that includes such a chip, SoC, chipset, package or device as well asat least one antenna (such as the antennas 620).

The wireless communication device 2100 includes a reception component2110, a communication manager 2120, and a transmission component 2130.The communication manager 2120 further includes a coordinated accesscomponent 2122. Portions of the coordinated access component 2122 may beimplemented at least in part in hardware or firmware. In someimplementations, the coordinated access component 2122 is implemented atleast in part as software stored in the memory. For example, portions ofthe coordinated access component 2122 can be implemented asnon-transitory instructions (or “code”) executable by the processor toperform the functions or operations of the respective component.

The reception component 2110 is configured to receive RX signalsrepresenting uplink communications from wireless stations orcommunications from other APs. The transmission component 2130 isconfigured to transmit TX signals representing downlink communicationsto the wireless stations or communications to other APs. In someimplementations, the coordinated access component 2122 is configured toreceive, via the reception component 2110, a first wireless packet froma second wireless access point that indicates that a plurality of timeand frequency resources of a transmission opportunity owned by thesecond wireless access point can be shared by the second wireless accesspoint. The coordinated access component 2122 also is configured togenerate and cause the transmission component 2130 to transmit a secondwireless packet to the second wireless access point indicating a desireto participate in the transmission opportunity. The coordinated accesscomponent 2122 also is configured to receive, via the receptioncomponent 2110, a third wireless packet from the second wireless accesspoint that includes an indication of a first set of time and frequencyresources of the plurality of time and frequency resources allocated tothe first wireless access point and usable by the first wireless accesspoint to transmit data to, or receive data from, a first set of wirelessstations in a first BSS controlled by the first wireless access pointduring the transmission opportunity. The coordinated access component2122 also is configured to allocate a first subset of time and frequencyresources, of the first set of time and frequency resources allocated tothe first wireless access point, to the first set of wireless stationsfor direct wireless communications with other wireless stations. Thecoordinated access component 2122 is additionally configured to generateand cause the transmission component 2130 to transmit a fourth wirelesspacket to the first set of wireless stations that includes an indicationof the first subset of time and frequency resources. The coordinatedaccess component 2122 is further configured to refrain from causing thetransmission component 2130 to transmit wireless communications in thefirst subset of time and frequency resources.

FIG. 22 shows a block diagram of an example wireless communicationdevice 2200 that supports coordinated D2D communications according tosome implementations. In some implementations, the wirelesscommunication device 2200 is configured to perform the process 1500described above with reference to FIG. 15. The wireless communicationdevice 2200 may be an example implementation of the wirelesscommunication device 500 described above with reference to FIG. 5. Forexample, the wireless communication device 2200 can be a chip, SoC,chipset, package or device that includes at least one modem (forexample, a Wi-Fi (IEEE 802.11) modem or a cellular modem such as themodem 502), at least one processor (such as the processor 504) and atleast one memory (such as the memory 508). The wireless communicationdevice 2200 may further include at least one radio (such as the radio506). In some implementations, the wireless communication device 2200can be a device for use in a STA, such as one of the STAs 104 and 604described above with reference to FIGS. 1 and 6A, respectively. In someother implementations, the wireless communication device 2200 can be aSTA that includes such a chip, SoC, chipset, package or device as wellas at least one antenna (such as the antennas 625).

The wireless communication device 2200 includes a reception component2210, a communication manager 2220, and a transmission component 2230.The communication manager 2220 further includes a coordinated accesscomponent 2222. Portions of the coordinated access component 2222 may beimplemented at least in part in hardware or firmware. In someimplementations, the coordinated access component 2222 is implemented atleast in part as software stored in the memory. For example, portions ofthe coordinated access component 2222 can be implemented asnon-transitory instructions (or “code”) executable by the processor toperform the functions or operations of the respective component.

The reception component 2210 is configured to receive RX signalsrepresenting downlink communications from a wireless access point orcommunications directly from other wireless stations. The transmissioncomponent 1930 is configured to transmit TX signals representing uplinkcommunications to the wireless access point or communications directlyto other wireless stations. In some implementations, the coordinatedaccess component 2222 is configured to receive, via the receptioncomponent 2210, a first wireless packet from a first wireless accesspoint that controls a first BSS including a first set of wirelessstations that includes the first wireless station, the first set ofwireless stations being configured for direct wireless communicationswith other wireless stations. The first wireless packet may include anindication of a first subset of time and frequency resources of a firstset of time and frequency resources allocated to the first BSS of aplurality of sets of time and frequency resources of a transmissionopportunity owned by the first wireless access point or a secondwireless access point, the first subset of time and frequency resourcesbeing allocated for use by the first set of wireless stations for directwireless communications with other wireless stations. The coordinatedaccess component 2222 is further configured to generate and cause thetransmission component 2230 to transmit a second wireless packetdirectly to another wireless station using the first subset of time andfrequency resources.

FIG. 23 shows a block diagram of an example wireless communicationdevice 2300 that supports coordinated D2D communications according tosome implementations. In some implementations, the wirelesscommunication device 2300 is configured to perform the process 1600described above with reference to FIG. 16. The wireless communicationdevice 2300 may be an example implementation of the wirelesscommunication device 500 described above with reference to FIG. 5. Forexample, the wireless communication device 2300 can be a chip, SoC,chipset, package or device that includes at least one modem (forexample, a Wi-Fi (IEEE 802.11) modem or a cellular modem such as themodem 502), at least one processor (such as the processor 504) and atleast one memory (such as the memory 508). The wireless communicationdevice 2300 may further include at least one radio (such as the radio506). In some implementations, the wireless communication device 2300can be a device for use in an AP, such as one of the APs 102 and 602described above with reference to FIGS. 1 and 6A, respectively. In someother implementations, the wireless communication device 2300 can be anAP that includes such a chip, SoC, chipset, package or device as well asat least one antenna (such as the antennas 620).

The wireless communication device 2300 includes a reception component2310, a communication manager 2320, and a transmission component 2330.The communication manager 2320 further includes a coordinated accesscomponent 2322. Portions of the coordinated access component 2322 may beimplemented at least in part in hardware or firmware. In someimplementations, the coordinated access component 2322 is implemented atleast in part as software stored in the memory. For example, portions ofthe coordinated access component 2322 can be implemented asnon-transitory instructions (or “code”) executable by the processor toperform the functions or operations of the respective component.

The reception component 2310 is configured to receive RX signalsrepresenting uplink communications from wireless stations orcommunications from other APs. The transmission component 2330 isconfigured to transmit TX signals representing downlink communicationsto the wireless stations or communications to other APs. In someimplementations, the coordinated access component 2322 is configured to,via the reception component 2310 and the transmission component 2330,exchange one or more first wireless packets with a first set of wirelessaccess points that includes the first wireless access point tocoordinate a schedule of periodic coordinated access windows duringwhich the first set of wireless access points are scheduled to contendfor access to one or more wireless channels. The coordinated accesscomponent 2322 also is configured to generate and cause the transmissioncomponent 2330 to transmit a second wireless packet that includes afirst indication of the periodic coordinated access windows. Thecoordinated access component 2322 also is configured to determine that afirst set of wireless stations in a first BSS controlled by the firstwireless access point is operating a NAN network, each wireless stationin the first set of wireless stations being configured for directwireless communications with other wireless stations in the NAN network.In some implementations, the first set of wireless stations are notpermitted to contend for access to the one or more wireless channelsduring the periodic coordinated access windows. The coordinated accesscomponent 2322 is additionally configured to generate and cause thetransmission component 2330 to transmit a third wireless packet to thefirst set of wireless stations that includes a second indication of areserved access window within one or more of the periodic coordinatedaccess windows, the second indication indicating that the first set ofwireless stations are permitted to transmit direct wirelesscommunications to other wireless stations in the NAN network on the oneor more wireless channels despite the first indication. The coordinatedaccess component 2322 is further configured to refrain from causing thetransmission component 2330 to transmit wireless communications duringthe reserved access windows.

FIG. 24 shows a block diagram of an example wireless communicationdevice 2400 that supports coordinated D2D communications according tosome implementations. In some implementations, the wirelesscommunication device 2400 is configured to perform the process 1700described above with reference to FIG. 17. The wireless communicationdevice 2400 may be an example implementation of the wirelesscommunication device 500 described above with reference to FIG. 5. Forexample, the wireless communication device 2400 can be a chip, SoC,chipset, package or device that includes at least one modem (forexample, a Wi-Fi (IEEE 802.11) modem or a cellular modem such as themodem 502), at least one processor (such as the processor 504) and atleast one memory (such as the memory 508). The wireless communicationdevice 2400 may further include at least one radio (such as the radio506). In some implementations, the wireless communication device 2400can be a device for use in a STA, such as one of the STAs 104 and 604described above with reference to FIGS. 1 and 6A, respectively. In someother implementations, the wireless communication device 2400 can be aSTA that includes such a chip, SoC, chipset, package or device as wellas at least one antenna (such as the antennas 625).

The wireless communication device 2400 includes a reception component2410, a communication manager 2420, and a transmission component 2430.The communication manager 2420 further includes a coordinated accesscomponent 2422. Portions of the coordinated access component 2422 may beimplemented at least in part in hardware or firmware. In someimplementations, the coordinated access component 2422 is implemented atleast in part as software stored in the memory. For example, portions ofthe coordinated access component 2422 can be implemented asnon-transitory instructions (or “code”) executable by the processor toperform the functions or operations of the respective component.

The reception component 2410 is configured to receive RX signalsrepresenting downlink communications from a wireless access point orcommunications directly from other wireless stations. The transmissioncomponent 2430 is configured to transmit TX signals representing uplinkcommunications to the wireless access point or communications directlyto other wireless stations. In some implementations, the coordinatedaccess component 2422 is configured to form or join a NAN networkincluding a first set of wireless stations that includes the firstwireless station, each wireless station in the first set of wirelessstations being configured for direct wireless communications with otherwireless stations in the NAN network. The coordinated access component2422 also is configured to receive, via the reception component 2410, afirst wireless packet from a first wireless access point that controls afirst BSS that includes the first set of wireless stations. The firstwireless packet may include a first indication of periodic coordinatedaccess windows during which wireless access points, including the firstwireless access point, are scheduled to contend for access to one ormore wireless channels, and during which wireless stations, includingthe first set of wireless stations, are not permitted to contend foraccess to the one or more wireless channels. The coordinated accesscomponent 2422 is additionally configured to receive, via the receptioncomponent 2410, a second wireless packet from the first wireless accesspoint that includes a second indication of a reserved access windowwithin one or more of the periodic coordinated access windows, thesecond indication indicating that the first set of wireless stations arepermitted to transmit direct wireless communications to other wirelessstations in the NAN network on the one or more wireless channels despitethe first indication. The coordinated access component 2422 is furtherconfigured to generate and cause the transmission component 2430 totransmit a third wireless packet directly to another wireless stationduring at least one of the reserved access windows.

As used herein, “or” is used intended to be interpreted in the inclusivesense, unless otherwise explicitly indicated. For example, “a or b” mayinclude a only, b only, or a combination of a and b. As used herein, aphrase referring to “at least one of” or “one or more of” a list ofitems refers to any combination of those items, including singlemembers. For example, “at least one of: a, b, or c” is intended to coverthe possibilities of: a only, b only, c only, a combination of a and b,a combination of a and c, a combination of b and c, and a combination ofa and b and c.

The various illustrative components, logic, logical blocks, modules,circuits, operations and algorithm processes described in connectionwith the implementations disclosed herein may be implemented aselectronic hardware, firmware, software, or combinations of hardware,firmware or software, including the structures disclosed in thisspecification and the structural equivalents thereof. Theinterchangeability of hardware, firmware and software has been describedgenerally, in terms of functionality, and illustrated in the variousillustrative components, blocks, modules, circuits and processesdescribed above. Whether such functionality is implemented in hardware,firmware or software depends upon the particular application and designconstraints imposed on the overall system.

Various modifications to the implementations described in thisdisclosure may be readily apparent to persons having ordinary skill inthe art, and the generic principles defined herein may be applied toother implementations without departing from the spirit or scope of thisdisclosure. Thus, the claims are not intended to be limited to theimplementations shown herein, but are to be accorded the widest scopeconsistent with this disclosure, the principles and the novel featuresdisclosed herein.

Additionally, various features that are described in this specificationin the context of separate implementations also can be implemented incombination in a single implementation. Conversely, various featuresthat are described in the context of a single implementation also can beimplemented in multiple implementations separately or in any suitablesubcombination. As such, although features may be described above asacting in particular combinations, and even initially claimed as such,one or more features from a claimed combination can in some cases beexcised from the combination, and the claimed combination may bedirected to a subcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. Further, the drawings may schematically depict one or moreexample processes in the form of a flowchart or flow diagram. However,other operations that are not depicted can be incorporated in theexample processes that are schematically illustrated. For example, oneor more additional operations can be performed before, after,simultaneously, or between any of the illustrated operations. In somecircumstances, multitasking and parallel processing may be advantageous.Moreover, the separation of various system components in theimplementations described above should not be understood as requiringsuch separation in all implementations, and it should be understood thatthe described program components and systems can generally be integratedtogether in a single software product or packaged into multiple softwareproducts.

1. A method for wireless communication by a first wireless access pointcomprising: transmitting a first wireless packet to at least a first setof wireless stations in a first basic service set (BSS) controlled bythe first wireless access point, each wireless station in the first setof wireless stations being configured for direct wireless communicationswith other wireless stations, the first wireless packet including anindication of periodic reserved access windows indicating to the firstset of wireless stations that they are permitted to transmit directwireless communications to other wireless stations in the first set ofwireless stations on one or more wireless channels during the periodicreserved access windows; and refraining from transmitting wirelesscommunications during the periodic reserved access windows.
 2. Themethod of claim 1, wherein the first wireless packet includes one ormore target wake time (TWT) information elements (IEs), each TWT IEincluding an indication of a schedule of wake periods, at least one ofthe TWT IEs including the indication of the periodic reserved accesswindows, the indication of the periodic reserved access windowsindicating that each of the wake periods in the respective schedule ofwake periods is a periodic reserved access window.
 3. The method ofclaim 2, wherein the at least one TWT IE includes an indication of atime slot schedule defining a series of time slots in the periodicreserved access windows, the method further comprising allocating eachof one or more of the time slots to a respective subset of the first setof wireless stations, each subset of wireless stations in the first setof wireless stations not being permitted to transmit direct wirelesscommunications in another time slot allocated to a different subset ofwireless stations in the first set of wireless stations.
 4. The methodof claim 3, wherein, during at least one time slot of the one or moretime slots included in the reserved access windows, one or more wirelessstations in the first set of wireless stations are permitted to transmitor receive direct wireless communications to or from other wirelessstations associated with one or more of the selected wireless accesspoints.
 5. The method of claim 4, further comprising: transmitting, toat least one of the selected wireless access points, identifiers of oneor more wireless stations in the first set of wireless stations; andreceiving, from the at least one selected wireless access point,identifiers of one or more wireless stations associated with the atleast one selected wireless access point that are configured for directwireless communications with other wireless stations; and coordinating,with the at least one selected wireless access point, one or both of:which wireless stations of the first set of wireless stations arepermitted to transmit direct wireless communications to wirelessstations associated with the at least one selected wireless access pointduring one or more time slots in the set of time and frequency resourcesallocated to the at least one selected wireless access point; and whichwireless stations of the set of wireless stations associated with the atleast one selected wireless access point are permitted to transmitdirect wireless communications to wireless stations in the first set ofwireless stations during one or more of the time slots in the firstsubset of time and frequency resources allocated to the first set ofwireless stations.
 6. The method of claim 4, wherein at least one timeslot of the one or more time slots associated with the first subset oftime and frequency resources corresponds to a respective time slot ineach of one or more other sets of time and frequency resources of theplurality of sets of time and frequency resources allocated to theselected wireless access points, and wherein each wireless station inthe first set of wireless stations and each wireless station in othersets of wireless stations associated with the selected wireless accesspoints is permitted to transmit direct wireless communications to eachof the other wireless stations during the at least one time slot and thecorresponding time slots.
 7. The method of claim 2, wherein the at leastone TWT IE includes: an individual TWT including an address of onewireless station in the first set of wireless stations; or a broadcastTWT identifying the entire first set of wireless stations.
 8. The methodof claim 1, further comprising transmitting a trigger frame or a reversedirection grant (RDG) to the first set of wireless stations, the triggerframe or the RDG initiating direct wireless communications by thewireless stations in the first set of wireless stations.
 9. A method forwireless communication by a first wireless station, the methodcomprising: receiving a first wireless packet from a first wirelessaccess point that controls a first basic service set (BSS) including afirst set of wireless stations that includes the first wireless station,the first wireless station being configured for direct wirelesscommunications with other wireless stations, the first wireless packetincluding an indication of periodic reserved access windows indicatingto the first wireless station that it is permitted to transmit directwireless communications to one or more other wireless stations in thefirst set of wireless stations on one or more wireless channels duringthe periodic reserved access windows; and transmitting a second wirelesspacket directly to another wireless station during at least one of theperiodic reserved access windows.
 10. The method of claim 9, wherein thefirst wireless packet includes one or more target wake time (TWT)information elements (IEs), each TWT IE including an indication of aschedule of wake periods, at least one of the TWT IEs including theindication of the periodic reserved access windows, the indication ofthe periodic reserved access windows indicating that each of the wakeperiods in the respective schedule of wake periods is a periodicreserved access window, the wake periods including the at least oneperiodic reserved access window.
 11. The method of claim 10, wherein theat least one TWT IE includes an indication of a time slot scheduledefining a series of time slots in the at least one periodic reservedaccess window, the method further comprising receiving an indicationthat at least one of the time slots is allocated to the first wirelessstation, or a group of wireless stations in the first set of wirelessstations that includes the first wireless station, each of the firstwireless station or the group of wireless stations not being permittedto transmit direct wireless communications in another time slotallocated to a different subset of wireless stations in the first set ofwireless stations.
 12. The method of claim 9, wherein the indicationindicates to the first wireless station that it is permitted to transmitdirect wireless communications to other wireless stations outside of thefirst set of wireless stations during at least a portion of one or moreof the periodic reserved access windows.
 13. The method of claim 9,further comprising: receiving a trigger frame or a reverse directiongrant (RDG) from the first wireless access point; and transmitting thesecond wireless packet in response to the reception of the trigger frameor the RDG.
 14. A method for wireless communication by a first wirelessaccess point, the method comprising: obtaining a transmissionopportunity for wireless communication via one or more wirelesschannels; selecting one or more other wireless access points toparticipate in the transmission opportunity; allocating a respective setof time and frequency resources of a plurality of sets of time andfrequency resources of the transmission opportunity to each of the firstwireless access point and the selected wireless access points;allocating a first subset of time and frequency resources, of the set oftime and frequency resources allocated to the first wireless accesspoint, to a first set of wireless stations in a basic service set (BSS)controlled by the first wireless access point for direct wirelesscommunications with other wireless stations; transmitting a firstwireless packet to the one or more selected wireless access points thatincludes, for each of the selected wireless access points, an indicationof the set of time and frequency resources allocated to the respectivewireless access point; transmitting a second wireless packet to thefirst set of wireless stations that includes an indication of the firstsubset of time and frequency resources; and refraining from transmittingwireless communications in the first subset of time and frequencyresources.
 15. The method of claim 14, wherein: the frequency resourcesin each set of time and frequency resources of the plurality of sets oftime and frequency resources overlap with the frequency resources in theother sets of time and frequency resources; the time resources in eachset of time and frequency resources of the plurality of sets of time andfrequency resources do not overlap with any of the time resources in theother sets of time and frequency resources; the time resources in theset of time and frequency resources allocated to the first wirelessaccess point include a plurality of time slots and the first subset oftime and frequency resources includes one or more of the plurality oftime slots; and the indication of the first subset of time and frequencyresources includes an indication of a time slot schedule for theplurality of time slots.
 16. The method of claim 15, wherein, during atleast one time slot of the one or more time slots included in the firstsubset of time and frequency resources, one or more wireless stations inthe first set of wireless stations are permitted to transmit or receivedirect wireless communications to or from other wireless stationsassociated with one or more of the selected wireless access points. 17.The method of claim 15, further comprising: transmitting, to at leastone of the selected wireless access points, identifiers of one or morewireless stations in the first set of wireless stations; receiving, fromthe at least one selected wireless access point, identifiers of one ormore wireless stations associated with the at least one selectedwireless access point that are configured for direct wirelesscommunications with other wireless stations; and coordinating, with theat least one selected wireless access point, one or both of: whichwireless stations of the first set of wireless stations are permitted totransmit direct wireless communications to wireless stations associatedwith the at least one selected wireless access point during one or moretime slots in the set of time and frequency resources allocated to theat least one selected wireless access point; and which wireless stationsof the set of wireless stations associated with the at least oneselected wireless access point are permitted to transmit direct wirelesscommunications to wireless stations in the first set of wirelessstations during one or more of the time slots in the first subset oftime and frequency resources allocated to the first set of wirelessstations.
 18. The method of claim 15, wherein at least one time slot ofthe one or more time slots associated with the first subset of time andfrequency resources corresponds to a respective time slot in each of oneor more other sets of time and frequency resources of the plurality ofsets of time and frequency resources allocated to the selected wirelessaccess points, and wherein each wireless station in the first set ofwireless stations and each wireless station in other sets of wirelessstations associated with the selected wireless access points ispermitted to transmit direct wireless communications to each of theother wireless stations during the at least one time slot and thecorresponding time slots.
 19. The method of claim 15, wherein the secondwireless packet includes a trigger frame that indicates the time slotschedule and that initiates direct wireless communications by wirelessstations in the first set of wireless stations.
 20. The method of claim14, wherein: the time resources in each set of time and frequencyresources of the plurality of sets of time and frequency resourcesoverlap with the time resources in the other sets of time and frequencyresources; the frequency resources in each set of time and frequencyresources of the plurality of sets of time and frequency resources donot overlap with any of the frequency resources in the other sets oftime and frequency resources; the frequency resources in each set oftime and frequency resources of the plurality of sets of time andfrequency resources of the transmission opportunity include a pluralityof frequency slots and the first subset of time and frequency resourcesincludes one or more of the plurality of frequency slots; and therespective indication of the set of time and frequency resourcesincludes an indication of a bandwidth schedule for the plurality offrequency slots.
 21. The method of claim 20, wherein, in at least onefrequency slot of the one or more frequency slots included in the firstsubset of time and frequency resources, one or more wireless stations inthe first set of wireless stations are permitted to transmit or receivedirect wireless communications to or from other wireless stationsassociated with one or more of the selected wireless access points. 22.The method of claim 20, further comprising: transmitting, to at leastone of the selected wireless access points, identifiers of one or morewireless stations in the first set of wireless stations; receiving, fromthe at least one selected wireless access point, identifiers of one ormore wireless stations associated with the at least one selectedwireless access point that are configured for direct wirelesscommunications with other wireless stations; and coordinating, with theat least one selected wireless access point, one or both of: whichwireless stations of the first set of wireless stations are permitted totransmit direct wireless communications to wireless stations associatedwith the at least one selected wireless access point in one or morefrequency slots in the set of time and frequency resources allocated tothe at least one selected wireless access point; and which wirelessstations of the set of wireless stations associated with the at leastone selected wireless access point are permitted to transmit directwireless communications to wireless stations in the first set ofwireless stations in one or more of the frequency slots in the firstsubset of time and frequency resources allocated to the first set ofwireless stations.
 23. The method of claim 20, wherein at least onefrequency slot of the one or more frequency slots associated with thefirst subset of time and frequency resources corresponds to a respectivefrequency slot in each of one or more other sets of time and frequencyresources of the plurality of sets of time and frequency resourcesallocated to the selected wireless access points, and wherein eachwireless station in the first set of wireless stations and each wirelessstation in other sets of wireless stations associated with the selectedwireless access points is permitted to transmit direct wirelesscommunications to each of the other wireless stations in the at leastone frequency slot and the corresponding frequency slots.
 24. The methodof claim 20, wherein the second wireless packet includes a trigger framethat indicates the bandwidth schedule and that initiates direct wirelesscommunications by wireless stations in the first set of wirelessstations.
 25. A method for wireless communication by a first wirelessaccess point, the method comprising: receiving a first wireless packetfrom a second wireless access point that indicates that a plurality oftime and frequency resources of a transmission opportunity owned by thesecond wireless access point can be shared by the second wireless accesspoint; transmitting a second wireless packet to the second wirelessaccess point indicating a desire to participate in the transmissionopportunity; receiving a third wireless packet from the second wirelessaccess point that includes an indication of a first set of time andfrequency resources of the plurality of time and frequency resourcesallocated to the first wireless access point and usable by the firstwireless access point to transmit data to, or receive data from, a firstset of wireless stations in a first basic service set (BSS) controlledby the first wireless access point during the transmission opportunity;allocating a first subset of time and frequency resources, of the firstset of time and frequency resources allocated to the first wirelessaccess point, to the first set of wireless stations for direct wirelesscommunications with other wireless stations; transmitting a fourthwireless packet to the first set of wireless stations that includes anindication of the first subset of time and frequency resources; andrefraining from transmitting wireless communications in the first subsetof time and frequency resources.
 26. The method of claim 25, wherein:the frequency resources in each set of time and frequency resources ofthe plurality of sets of time and frequency resources overlap with thefrequency resources in the other sets of time and frequency resources;the time resources in each set of time and frequency resources of theplurality of sets of time and frequency resources do not overlap withany of the time resources in the other sets of time and frequencyresources; the time resources in the set of time and frequency resourcesallocated to the first wireless access point include a plurality of timeslots and the first subset of time and frequency resources includes oneor more of the plurality of time slots; and the indication of the firstsubset of time and frequency resources includes an indication of a timeslot schedule for the plurality of time slots.
 27. The method of claim26, wherein, during at least one time slot of the one or more time slotsincluded in the first subset of time and frequency resources, one ormore wireless stations in the first set of wireless stations arepermitted to transmit or receive direct wireless communications to orfrom other wireless stations associated with one or more of the selectedwireless access points.
 28. The method of claim 26, further comprising:transmitting, to the first wireless access point, identifiers of one ormore wireless stations in the first set of wireless stations; receiving,from the second wireless access point, identifiers of one or morewireless stations associated with the second wireless access point thatare configured for direct wireless communications with other wirelessstations; and coordinating, with the second wireless access point, oneor both of: which wireless stations in the first set of wirelessstations are permitted to transmit direct wireless communications towireless stations associated with the second wireless access pointduring one or more time slots in the set of time and frequency resourcesallocated to the second wireless access point; and which wirelessstations of the set of wireless stations associated with the secondwireless access point are permitted to transmit direct wirelesscommunications to wireless stations in the first set of wirelessstations during one or more of the time slots in the first subset oftime and frequency resources allocated to the first set of wirelessstations.
 29. The method of claim 26, wherein at least one time slot ofthe one or more time slots associated with the first subset of time andfrequency resources corresponds to a respective time slot in each of oneor more other sets of time and frequency resources of the plurality ofsets of time and frequency resources allocated to one or more otherwireless access points, and wherein each wireless station in the firstset of wireless stations and each wireless station in other sets ofwireless stations associated with the other wireless access points ispermitted to transmit direct wireless communications to each of theother wireless stations during the at least one time slot and thecorresponding time slots.
 30. The method of claim 27, wherein the fourthwireless packet includes a trigger frame that indicates the time slotschedule and that initiates direct wireless communications by wirelessstations in the first set of wireless stations.
 31. The method of claim25, wherein: the time resources in each set of time and frequencyresources of the plurality of sets of time and frequency resourcesoverlap with the time resources in the other sets of time and frequencyresources; the frequency resources in each set of time and frequencyresources of the plurality of sets of time and frequency resources donot overlap with any of the frequency resources in the other sets oftime and frequency resources; the frequency resources in each set oftime and frequency resources of the plurality of sets of time andfrequency resources of the transmission opportunity include a pluralityof frequency slots and the first subset of time and frequency resourcesincludes one or more of the plurality of frequency slots; and therespective indication of the set of time and frequency resourcesincludes an indication of a bandwidth schedule for the plurality offrequency slots.
 32. The method of claims 31, wherein, in at least onefrequency slot of the one or more frequency slots included in the firstsubset of time and frequency resources, one or more wireless stations inthe first set of wireless stations are permitted to transmit or receivedirect wireless communications to or from other wireless stationsassociated with one or more of the selected wireless access points. 33.The method of claim 31, further comprising: transmitting, to the secondwireless access point, identifiers of one or more wireless stations inthe first set of wireless stations; receiving, from the second wirelessaccess point, identifiers of one or more wireless stations associatedwith the second wireless access point that are configured for directwireless communications with other wireless stations; and coordinating,with the second wireless access point, one or both of: which wirelessstations of the first set of wireless stations are permitted to transmitdirect wireless communications to wireless stations associated with thesecond wireless access point in one or more frequency slots in the setof time and frequency resources allocated to the second wireless accesspoint; and which wireless stations of the set of wireless stationsassociated with the second wireless access point are permitted totransmit direct wireless communications to wireless stations in thefirst set of wireless stations in one or more of the frequency slots inthe first subset of time and frequency resources allocated to the firstset of wireless stations.
 34. The method of claim 31, wherein at leastone frequency slot of the one or more frequency slots associated withthe first subset of time and frequency resources corresponds to arespective frequency slot in each of one or more other sets of time andfrequency resources of the plurality of sets of time and frequencyresources allocated to the selected wireless access points, and whereineach wireless station in the first set of wireless stations and eachwireless station in other sets of wireless stations associated with theselected wireless access points is permitted to transmit direct wirelesscommunications to each of the other wireless stations in the at leastone frequency slot and the corresponding frequency slots.
 35. The methodof claim 31, wherein the fourth wireless packet includes a trigger framethat indicates the bandwidth schedule and that initiates direct wirelesscommunications by wireless stations in the first set of wirelessstations. 36-100. (canceled)